X2Rail-1
Project Title: Start-up activities for Advanced Signalling and Automation Systems Starting date: 01/09/2016 Duration in months: 36 Call (part) identifier: H2020-S2RJU-CFM-2015-01-1 Grant agreement no: 730640
Deliverable D7.1 Analysis of existing lines and economic models
Due date of deliverable Month 09 Actual submission date 18-02-2019 Organization name of lead contractor for this deliverable 18-TTS Dissemination level PU Revision DB-001-02-R2
Deliverable template version: 02 (09/11/16) X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Authors
Author(s) Alstom Transport S.A. (ALS) Pierre Damien Jourdain AZD Praha SRO (AZD) Michal Pavel Lukas Michalik BOMBARDIER TRANSPORTATION SWEDEN AB (BTSE) Jorgen Mattisson INDRA (INDRA) Francisco Parrilla Thales Transportation Systems GMBH (TTS) Ana Millán Belen Losada Trafikverket – TRV (TRV) Jan Bystrom
Contributor(s) ANSALDO STS S.p.A. (ASTS) Giovanni Canepa
CAF Signalling S.L. (CAF) Ignacio Gonzalez
Deutsche Bahn AG (DB) Julian Mohr
MERMEC SPA (MERMEC) Vito Caliandro
Siemens (SIE) Jose Manuel Mellado
GA 730640 Page 2 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 1. Executive Summary
The present document constitutes the first issue of Deliverable D7.1 “Analysis of existing lines and economic models” in the framework of the Project titled “Start-up activities for Advanced Signalling and Automation Systems” (Project Acronym: X2Rail-1; Grant Agreement No 730640). Although modern signalling systems are going to considerably reduce trackside equipment in the next years, a source of the innovation step proposed by the X2Rail-1 WP7 is to provide fully distributed control of remote trackside objects such as points, level crossings, etc., without requiring the necessity to install specialized trackside cabling and associated cable routes, ducting etc. Additionally a higher data band-width in modern communication links could be used for transmission of status reports/maintenance information and further required data. The Smart Wayside Object Controller (SWOC) is a piece of equipment that is directly connected to the Wayside Objects, on one side, and to the Route Management Systems (Interlocking, TMS, ATP, etc.), on the other side; and to other SWOCs. The SWOC manages control, maintenance and diagnosis data related to the Wayside Object; and may also supply power to them. The objective of this document is to analyse the existing lines and economic model from the perspective of the wayside objects, in order to demonstrate the soundness of the concept of object controllers (OCs) realizing a distributed approach to rail automation. The further objective is to analyse the state-of-the-art technologies for wireless data transmission, for power supply and energy harvesting and for maintenance and diagnosis. The main points to be achieved are: define and demonstrate feasibility of Smart wayside object controllers, connecting with communication networks (wireless, existing, public, etc.), using locally derived power supply, resulting in reducing power consumption, reduction of required cabling, enabling wireless data exchange with existing and/ or new TMS and enhanced availability of maintenance data. To reach them, the following activities have been carried out:
· Analyse the different economic models, from high performance lines to low density and geographical distributed, as could be freight and regional. · Analyse the state-of-the-art of wireless communication technologies · Analyse the state-of-the-art of technical possibilities within power supply area. Regarding this issue it has been relevant to have a look to two aspects: more effective power supply and reduction of power consumption in field elements themselves.
GA 730640 Page 3 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· Analyse the state-of-the-art of maintenance and diagnosis
From these different analyses we have been be able to obtain the results described in the following paragraphs: Even though Regional Rail lines ares the most convenient scenario where the proposal of SWOC is a priori approachable in economic terms; we can conclude that the distributed SWOC solution should be flexible enough to match the challenges and scalability of the new projects in all rail topologies. Concerning wireless communication technologies, we can expose that SWOC will be able to connect to different wireless networks as long as they are available in the area and meet the requirements needed according the application. Besides that, proprietary application of wireless links in different topologies can be deployed. The specific solution that ensures energy supply to a “self-sufficient smart object” depends on the configuration and power consumption of the object controller, on the environmental conditions for energy harvesting and on the mode of the railway line operation. After knowing high operating cost of any production system is caused by maintenance, maintainability of the product is the essence to assure the remote operability; provided by the wireless capability (power, wireless connection).
GA 730640 Page 4 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Table of Contents
1. EXECUTIVE SUMMARY ...... 3
2. ABBREVIATIONS AND ACRONYMS ...... 9
3. BACKGROUND ...... 16
4. PURPOSE AND OBJECTIVE...... 17
4.1. EXPECTED IMPACT OF THE “SMART WAYSIDE OBJECTS CONTROLLERS” ...... 20
5. ANALYSIS OF ECONOMIC MODELS ...... 22
5.1. OBJECTIVE ...... 22 5.2. TOPICS FOR THE ANALYSIS ...... 22 5.3. REPRESENTATIVE SCENARIOS ...... 24 5.3.1. Mainline/High-Speed Rail ...... 25 5.3.2. Urban / Metro ...... 26 5.3.3. Regional Rail ...... 27 5.3.4. Secondary Rail ...... 28 5.3.5. Station & Yard ...... 28 5.4. FACTORS INVOLVED (RAILWAY TECHNOLOGY) ...... 29 5.4.1. Type of WO ...... 29 5.4.2. Communication ...... 30 5.4.3. Power ...... 31 5.4.4. Diagnosis and Maintenance ...... 32 5.5. PROPOSED SCENARIO...... 32 5.6. ANALYSIS OF ECONOMIC MODELS ...... 34 5.6.1. Feasibility of SWOC ...... 35 5.6.2. Centralized & wired solutions vs Distributed & wireless solutions...... 37 5.6.3. Diagnosis and Maintenance ...... 38 5.6.4. OC/SWOC Power ...... 38 5.7. RESULT OF THE ANALYSIS ...... 40
6. ANALYSIS OF THE STATE-OF-THE-ART OF THE WIRELESS COMMUNICATION TECHNOLOGIES ...... 48
6.1. PURPOSE AND SCOPE ...... 48 6.2. OBJECTIVES ...... 48 6.3. WIRELESS COMMUNICATIONS TECHNOLOGIES ...... 49 6.3.1. Advantages & Disadvantages of Wireless Networks ...... 49 6.3.2. Available terrestrial wireless technologies ...... 51 6.3.2.1. Communications protocols...... 51 6.3.2.2. Communications application areas ...... 51 6.3.2.3. Evolution of terrestrial networks ...... 52 6.3.2.3.1. Data rate and ranges of wireless technologies ...... 55 6.3.2.4. IEEE 802.11 family ...... 55 6.3.2.4.1. IEEE 802.11a/b/g/n/ac (WiFi) ...... 55
GA 730640 Page 5 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
6.3.2.4.2. Standard 802.11ah (HayLow) ...... 57 6.3.2.4.3. Standard 802.11p (ETSI ITS-G5) ...... 59 6.3.2.4.4. IEEE 802.15.1 (Bluetooth) ...... 60 6.3.2.5. IEEE 802.15.4...... 61 6.3.2.5.1. 802.15.4 ZigBee ...... 62 6.3.2.5.2. 6LoWPAN ...... 63 6.3.2.5.3. Thread ...... 64 6.3.2.6. WiMAX (IEEE 802.16) ...... 65 6.3.2.7. Z-Wave ...... 67 6.3.2.8. EnOcean ...... 69 6.3.3. Mobile Cellular Networks ...... 71 6.3.3.1. Basics ...... 71 6.3.3.1.1. Spectrum Usage ...... 72 6.3.3.1.2. Cell signal encoding ...... 72 6.3.3.1.3. Structure of the cellular network ...... 73 6.3.3.1.4. Cellular handover ...... 73 6.3.3.1.5. Coverage comparison ...... 74 6.3.3.2. Circuit Switched Data Services in GSM...... 74 6.3.3.2.1. Basic and High-speed CS data transmission...... 74 6.3.3.2.2. GPRS (General Packet Radio Service) ...... 74 6.3.3.2.3. UMTS and IMT-2000...... 75 6.3.3.3. Evolved High Speed Packet Access (HSPA, HSPA+) ...... 77 6.3.3.4. High Speed Downlink Packet Access (HSDPA) ...... 77 6.3.3.5. Long-Term Evolution (LTE) ...... 78 6.3.3.5.1. Frequency bands ...... 79 6.3.4. IoT Wide-Area Networks ...... 79 6.3.4.1. LoRaWAN ...... 80 6.3.4.2. Symphony Link ...... 82 6.3.4.3. NarrowBand IoT (NB-IoT) ...... 83 6.3.4.4. UNB/Sigfox ...... 85 6.3.5. Satellite technologies and services ...... 87 6.3.5.1. GEO L-band satellite services application for Railway Signalling ...... 89 6.3.5.2. GEO S-band prototype services for buses and trucks ...... 90 6.3.5.3. New LEO services from IRIDIUM, GOOGLE and alternatives ...... 91 6.3.5.3.1. IRIDIUM ...... 92 6.3.5.3.2. GOOGLE ...... 92 6.3.5.3.3. Airbus Defence and Space ...... 93 6.3.5.3.4. ORBCOMM ...... 94 6.3.5.4. New GEO services ...... 95 6.3.5.4.1. Global Xpress ...... 95 6.3.5.4.2. BATS ...... 95 6.4. COMMUNICATION SECURITY ...... 96 6.4.1. General information ...... 96 6.4.2. IPSec as COMSEC for the internet ...... 97 6.4.3. Security for Railways...... 98 6.4.4. Existing Communication security features in LTE ...... 102 6.4.4.1. Security overview...... 102
GA 730640 Page 6 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
6.4.4.2. Concept of separation of the communication planes ...... 103 6.4.4.3. Security mechanism ...... 105 6.4.4.3.1. About the SIM cards ...... 105 6.4.4.3.2. About the Air Interface Protection ...... 105 6.4.4.3.3. About the IP Backhaul Protection ...... 108 6.4.5. Existing Communication security features in 802.11 family and variants ...... 110 6.4.6. Existing Communication security features in SATCOM ...... 113 6.4.6.1. Security overview...... 113 6.4.6.2. Security mechanism and related initiatives in progress ...... 114 6.4.6.3. Conclusion ...... 115 6.4.7. Impact for IP COMM SYSTEM ...... 116 6.4.7.1. Transmission security features in each technology ...... 116 6.4.7.2. Summary of Communication Security features in each technology...... 117 6.4.7.3. Limitations of the countermeasures against Deny of Service ...... 118 6.5. NETWORK PROVIDERS ...... 120 6.5.1. Public ...... 120 6.5.2. Private...... 121 6.6. SPECTRUM MANAGEMENT ...... 121 6.6.1. Free frequency bands...... 121 6.6.2. Licensed frequency bands ...... 122 6.7. TECHNICAL REQUIREMENTS AND CHARACTERISTICS ...... 123 6.7.1. Data bandwidth/throughput and timing latency ...... 123 6.7.2. Distance ranges ...... 126 6.7.3. Power consumption ...... 126 6.7.4. Transmission dependability...... 127 6.7.5. Line security ...... 127 6.8. MAINTENANCE ...... 127 6.9. RESULT OF THE ANALYSIS ...... 128
7. ANALYSIS OF THE STATE-OF-THE-ART OF POWER SUPPLY ...... 132
7.1. PURPOSE AND SCOPE ...... 132 7.2. OBJECTIVES ...... 132 7.3. POWER CONSUMPTION...... 133 7.3.1. General ...... 133 7.3.2. Object Controller ...... 136 7.3.3. Field Elements ...... 136 7.3.4. Reduction of Power Consumption ...... 138 7.4. ENERGY HARVESTING ...... 138 7.4.1. General ...... 138 7.4.2. Catenary ...... 139 7.4.3. Solar Energy ...... 139 7.4.4. Wind Energy ...... 139 7.4.5. Fuel Cell ...... 139 7.4.6. Re-generating Energy ...... 140 7.4.7. Availability of Energy Sources and System Design ...... 140 7.5. ENERGY STORAGE ...... 143 7.5.1. General ...... 143
GA 730640 Page 7 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
7.5.2. Capacitors and Supercapacitors ...... 143 7.5.3. Batteries...... 144 7.5.3.1. Conventional Batteries...... 144 7.5.3.2. Future Batteries ...... 146 7.6. SUPERVISION AND MAINTENANCE ...... 147 7.6.1. General ...... 147 7.6.2. Safety and Hazards ...... 148 7.7. RESULT OF THE ANALYSIS ...... 148
8. ANALYSIS OF THE STATE-OF-THE-ART OF MAINTENANCE AND DIAGNOSIS ...... 149
8.1. INTRODUCTION ...... 149 8.2. SCOPE - MOTIVATION ...... 150 8.3. RESEARCH PROJECTS IN THE SAME SCOPE ...... 153 8.3.1. Input from Infrastructure Innovation Program (IP3) ...... 153 8.4. PRODUCTS – RESULTS IN THE SCOPE OF THE STUDY ...... 153 8.5. POSITION OF THE COMPETITORS ...... 155 8.6. INTERFACES (NETWORK, PROTOCOL, CAPACITY, ETC.) ...... 156 8.6.1. Simple Network Management Protocol (SNMP) ...... 157 8.7. INPUTS FROM OTHER PROJECTS/DOMAINS ...... 159 8.8. RESULT OF THE ANALYSIS ...... 159
9. CONCLUSIONS ...... 160
10. REFERENCES ...... 162
11. APPENDICES ...... 165
GA 730640 Page 8 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 2. Abbreviations and acronyms
Abbreviation / Acronym Description
Successive Generations of digital cellular radio- 2G, 3G, 4G, 5G communications starting with GSM
6LoWPAN IPv6 Low power Wireless Personal Area Network
AES Advanced Encryption Standard (NIST)
AKA Authentication and Key Agreement (LTE)
AP Access point
BS Base Station
BSS Basic Service Set
Communications Access for Land Mobiles (ISO TC CALM 204 / WG 16)
CAPEX Capital Expenditure
CBC Cipher Block Chaining
CBM Condition Based Maintenance
CBTC Communication Based Train Control
CCMP Counter-Mode/CBC-Mac protocol (cryptography)
CDMA Code Division Multiple Access
CMMS Computerized Maintenance Management System
COMSEC Communication Security
Carrier Sense Multiple Access ( /Collision CSMA ( /CA) Avoidance)
DSRC Dedicated Short Range Communication
GA 730640 Page 9 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
DSSS Direct Sequence Spread Spectrum
EAP Extensible Authentication Protocol
EIRP Equivalent Isotropic Radiated Power
EM Electro-Magnetic
eNodeB Evolved Node B (Base Station of LTE networks)
EPC Evolved Packet Core
ERTMS European Rail Traffic Management System
Standards organization European ETSI Telecommunications Standards Institute
European Initiative Linking Interlocking EULYNX Subsystems
Evolved Universal Radio Access Network (Radio E-UTRAN access part of a LTE network)
FDMA Frequency Division Multiple Access
Frequency Hopping-Orthogonal Frequency FH-OFDM Division Multiplexing
FHSS Frequency Hopping Spread Spectrum
FRMCS Future Railway Mobile Communication System
European (ETSI) version of IEEE 802.11p (5 stands G5 for 5 GHz)
GEO GEOsynchronous Satellite
GNSS Global Navigation Satellite System
GPRS General Packet Radio Service (2G+ Cellular)
GPS Global Positioning System
GSM(-R) Global System for Mobiles(-Railway)
GA 730640 Page 10 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
GW Gateway
HSR High Speed Rail
HSS Home Subscriber Server
HW Hardware
IEC International Electrotechnical Commission
IEEE Institute of Electrical and Electronics Engineers
IETF Internet Engineering Task Force
IKE Internet Key Exchange protocol (for IPSec)
INFOSEC Information Security
IoT Internet of Things
IP Internet Protocol
IPSec IP Security
IPv4 Internet Protocol version 4
IPv6 Internet Protocol version 6
IR Infra-Red (light)
Infrared Data Association (industry interest group IRDA for IR communications)
ISO International Organisation for Standardisation
ITS Intelligent Transport Systems
LAN Local Area Network
LCC Life Cycle Cost
LMO Lithium-ion Manganese Oxide
LORA Long Range (IoT technology)
GA 730640 Page 11 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
LOS Line Of Sight
LRT Light Rapid Transit
Long Term Evolution (of 3G Cellular networks, LTE going to 4G)
MA Movement Authority
MAC Medium Access Control
MIB Management Information Base
MIMO Multiple Input Multiple Output (antennas)
MME Mobility Management Entity (LTE)
MR Mainline Rail
MRT Mass Rapid Transit
MTBF Mean Time Between Failures
MTBR Mean Time Between Repair
NAS Non-Access Stratum protocol (LTE)
NCA Lithium Nickel Cobalt Aluminium Oxide
NGTC European project Next Generation Train Control
NIST National Institute of Standards and Technology
OBU On Board Unit
OC Object Controller
OFDM Orthogonal Frequency Division Multiplexing
Open Platform Communications Unified OPC-UA Architecture
OPEX Operational Expenditure
GA 730640 Page 12 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
OSI Open Systems Interconnection (ISO 7498)
OTA Over-The-Air
PDCP Packet Data Convergence Protocol
PDN Packet Data Network
PIN Personal Identification Number
PKI Public Key Infrastructure
PMR Professional Mobile Radio
PPHPD Passengers Per Hour Per Direction
PS Packet Switched
QAM Quadrature Amplitude Modulation
QoS Quality of Service
RR Regional Rail
RRC Radio Resource Control (LTE)
RT Rapid Transit Railways
RTM Real Time Messaging
SATCOM Satellite Communications
SEG Security Gateways (3GPP abbreviation)
SIM Subscriber Identity Module
SWOC Smart Wayside Object Controller
SNMP Simple Network Management Protocol
SOA State-of-the-Art
SR Secondary Rail
GA 730640 Page 13 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
STANAG Standard Agreement (NATO)
TCP Transport Control Protocol (OSI L4)
TD Technology Demonstrator
TDD Time Division Duplex
TDMA Time Division Multiple Access
TMS Traffic Management System
TRL Technical Readiness Level
TVD Track Vacancy Detection
TX Transmitter
UE User Equipment (LTE)
UIC Union Internationale des Chemins de fer
Universal Mobile Telecommunications System (3G UMTS Cellular)
USIM UMTS Subscriber Identity Module
Ultra Wide Band (telecommunication in radar UWB mode)
VoIP Voice Over IP
VPN Virtual Private Network
Worldwide Interoperability for Microwave Access WIMAX (IEEE 802.16x)
WLAN Wireless Local Area Network
Wi-Fi Protected Access N°2 (IEEE 802.11i, in both WPA2 infra and Ad-hoc modes)
WPAN Wireless Personal Area Network
GA 730640 Page 14 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
WWAN Wireless Wide Area Network
Acronym for WLAN technology based on IEEE Wi-Fi 802.11
GA 730640 Page 15 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 3. Background
The present document constitutes the first issue of Deliverable D7.1 “Analysis of existing lines and economic models” in the framework of the project titled “Start-up activities for Advanced Signalling and Automation Systems” (Project Acronym: X2Rail-1; Grant Agreement No 730640). Shift2Rail (S2R) is the first joint European rail technology initiative, to seek focused research and innovation (R&I) and market-driven solutions. This can be achieved by accelerating the integration of new and advanced technologies into innovative rail product solutions. Shift2Rail will promote the competitiveness of the European Rail industry and will meet the changing EU transport needs. The R&I activities are carried out under the Horizon 2020 initiative and will develop the necessary technology to complete the Single European Railway Area (SERA). Further information can be found on http://shift2rail.org/. The X2Rail-1 project aims to research and develop six selected key technologies to foster innovations in the field of railway signalling and automation systems. The project is part of a longer term Shift2Rail IP2 strategy towards a flexible, real-time, intelligent traffic management and decision support system. In particular, Work Package 7 (WP7) “Smart wayside objects” focuses on the development of autonomous, complete, intelligent, self-sufficient smart equipment (“boxes”) able to connect with control centres (e.g. interlockings) and wayside objects and communicating devices in the area (by radio or satellite ), but also e.g. with on- board-units and TMS. This report is the deliverable of Task 7.2 (Analysis of existing lines and economic models) and therefore, the first deliverable of WP7.
GA 730640 Page 16 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 4. Purpose and Objective
This document is the product of X2RAIL-1 WP 7, Smart Wayside Objects, task 7.2, analysis of existing lines and economic models. In this task the participants have carried out the following activities:
· Analyse the different economic models, from high performance lines to low density and geographical distributed, as could be freight and regional. · Analyse the state-of-the-art of communication technologies · Analyse the state-of-the-art of technical possibilities within power supply area. Regarding this issue it has been relevant to have a look to two aspects: lower power supply and reduction of power consumption in field elements itself. · Analyse the state-of-the-art of Maintenance and Diagnosis · Document and report the results of all analysis accordingly.
The result of this task is this deliverable D7.1 “Analysis of existing lines and economic models”, and it is linked as an input for the further task 7.3 “Analysis of railway requirements and standards”, 7.4 “Definition of system architecture”, and the expertise activities to cover power supply models. The objective the document is to analyse the existing lines and economic model from the perspective of the wayside objects, in order to demonstrate the soundness of the concept of object controllers (OCs) realizing a decentralized approach to rail automation. This approach will be scalable from high performance lines to regional and freight lines application. Although modern signalling systems will have considerably reduced trackside equipment, decentralized solution is still attractive, as at least interfaces to points and level crossings will remain, and other necessary interfaces, depending on the specific application requirements. Today’s field-element controllers are designed and developed by each supplier in a different way. They are connected with copper – at least to be connected to the required power supply. The connection to Interlockings, Radio Block Centre, Automatic Blocks, Train Management Systems (TMS), etc. follows either rules or techniques of manufactures themselves or requirements given by railway authorities, not yet harmonised. Currently trackside objects are interfaced to control systems in one of two ways: a) Where trackside objects are fairly near signalling equipment, tail cables to individual objects are used;
GA 730640 Page 17 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
b) Where trackside objects are geographically distributed, Object Controllers (OCs) are placed near the trackside objects, controlling a number of them, with a data link back to the signalling equipment. There are disadvantages to these solutions:
· It is expensive to provide cabling for power and data to remote trackside objects, especially in freight lines or regional lines featured by light traffic.
· The cable provided is vulnerable to cable theft, which is costly, and causes disruption.
· Changes within track layouts (position of trackside equipment) are complex and costly.
· The usage of cable restricts distances between trackside objects and signalling equipment which might demand additional equipment.
An avoidance of all cabling in the field may reduce lifecycle costs of future railway projects, even significantly:
· Material costs
· Installation costs
· Maintenance costs
· Energy costs
· Cost occurring because of cable thefts
A solution, where locally derived power and radio communications (or any wireless network communication) and maintenance and diagnosis interface, together with maximum de-centralisation (up to the level of one OC for every individual trackside object) are used, may overcome these disadvantages and may improve reliability, improve capacity, lower investments, may reduce operating costs, improved standardisation and therefore simplified certification / authorisation. Beside the provision of local power supply, the challenge for a future demonstration project is to provide radio communications to individual remote trackside objects and guaranteeing safety and security justifications. The innovation is to provide fully de-centralized control of remote trackside objects such as points, level crossings, etc., without requiring the use of trackside cabling, and associated cable routes, ducting etc. Additionally the higher band width could be used for transmission of status reports / maintenance information and further required data (e. g. patches).
GA 730640 Page 18 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Cable free connections between objects/machines get more and more state-of-the-art. Existing devices mostly deal with less safety relevant information / applications. We have to assure on the one hand safety and security of data and on the other hand we have to implement energy harvesting systems – which have to be that reliable as it is requested by railway requirements. The Smart Wayside Object Controller (SWOC) is a piece of equipment that is directly connected to the Wayside Objects, on one side, and to the Route Management Systems (Interlocking, TMS, ATP, etc.), on the other side; and to other SWOCs. The SWOC manages control, maintenance and diagnosis data related to the Wayside Object; and may also supply power to them. Such intelligent objects controllers – knowing and communicating about their status conditions – would not only provide opportunities in terms of cost reduction and asset management improvement but also open new ways of railway network information management and control.
Figure 4.1 – Smart Wayside Object Controller
A detailed analysis of existing technical solutions / possibilities has been done and documented in the following chapters. Objectives to be achieved are:
· Smart wayside objects controllers radio-connected all-in-all
· Locally derived power supply
· Reduction of power consumptions
· Reduction of required cabling
· Data Exchange with existing and / or new Manage Routes Systems or TMS
· Availability of Maintenance Data
· Security and device protection
GA 730640 Page 19 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
4.1. Expected Impact of the “Smart Wayside Objects Controllers”
Objectives and expected Business Benefits as 1st step in Europe as 2nd step worldwide and Key Contribution is:
· Improved reliability thanks to cabling reduction because of the reduction of the risk of theft of cable.
· Higher availability and high dependability thanks to redundancy usually provided in wireless connections
· Reduced cost of deployment thanks to reduced need of cables. Only those for powering devices are necessary. Less cost of purchasing and installation of cables.
· Significantly lowering the effort for project specific engineering, installation and commissioning;
· Eliminating the cost for replacement of cables and related services caused by cable theft and civil works impacts;
· Using locally derived supply power yielding reduced energy losses via long tail cables and “green up” the transport;
· Overall objective is significant LCC reduction (Estimated value 50% in total – for freight and regional lines)
§ minimizing deployment of dedicated data communication cables and instead exploiting existing radio communication systems, public IP network access points or satellite communication systems § keeping the levels of safety and operational efficiency of signalling systems, while reducing investment costs; · Interfaces between Object Controllers and IXL or either train can be easily standardized in terms of physical and functional link. Open network and standard interfaces will produce interchangeability of OC and IXL.
· The maturity of the communication systems as such should be very high: TRL 5- 7 (The degree of maturity is strongly dependent on the outcomes of other TD, which will be implemented inside the OC which are e.g. the communication solutions, cyber security, and of the advances made in the locally derived power supply technologies).
GA 730640 Page 20 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Measurable quantities are life cycle costs:
· Basic invest – costs of cabling and material;
· Installation costs – complexity, expenditure of time, required man power;
· Maintenance cost (taking into account new hardware configuration as well as new functional possibilities with data exchange with TMS), MTBR, MTBF. Additionally, removal of cable maintenance and identification of cable problems should lead to lower costs.
· Cable theft;
· Engineering efforts – considering all the phases from planning, design to installation and commissioning.
As a consequence, first time in railway history the lifecycles of wayside objects and IXL can be separated and independent replacement based on individual life cycles will become true. Associated major cost savings by avoiding to replace interlocking and all linked wayside objects at the same time but to replace each one based on its individual life cycle.
GA 730640 Page 21 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 5. Analysis of economic models
5.1. Objective
The objective of this chapter is to analyse the possible scenario/s to be focused in, fix the business case/s, asses the value of the proposed solution, economical savings and technical coherence. This will be defined based on the existing technical solutions (proposed solution, state-of-the-art, etc...) and economic analysis (in terms of costs saving). To tackle the objective, it is necessary at a first phase, to collect information on different railway lines in operation with different characteristics concerning both CAPEX and OPEX phases relating to the supply, installation, operation and maintenance of field equipment, their interfaces and existing communication networks for railway signalling. With the information collected, the aim is to deduce the variables of interest that impact into the economic analysis, like equipment supply, maintenance, civil engineering works, etc. In the other hand, identify the different applying scenarios involving the railway business, as they are described in the chapter Fehler! Verweisquelle konnte nicht gefunden werden.. For the economic analysis, it will be considered the WO and OC density in the selected scenario as well as the distance between those elements (between OC and the Interlocking and between them and the existing Power sources). This is done in this way because deployment and installation costs depends on several factors as IM, vendor, installation purpose, country…, but all of them are related with amount of WO/OC (density) to be installed and distances from communication and power sources to the correspondent equipment (WO or OC). So that It is considered the density and distance as the factor for determining the costs reduction once the SWOC is deployed versus OC installation.
5.2. Topics for the Analysis
In order to achieve the objective of the document described in previous chapter it has been selected the following main topics into the possible cost reduction:
· Installation: It is defined as how certain technology impact in the development of an installation (the installation itself, as well as the development, configuration and parametrization of the system). This impact can be summarized as: o CAPEX deployment costs: § Civil works.
GA 730640 Page 22 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
§ Cabling (power and communication). o Tests costs: § FAT. § SAT. § Commisioning.
· Diagnosis and Maintenance OPEX costs: It is defined as how maintenance works (preventive and corrective works) impact in the maintenance of the installation. This impact can be summarized as: o Material (spare parts, cable,…): § Preventive maintenance. § Corrective maintenance. · Maintenance because cabling theft. · Maintenance because life cycle. o Update costs: § Software updates. § Firmware updates. o Human staff costs: § Task forces for preventive maintenance. § Staff rostering for corrective maintenance.
· Communications System: It is defined as how systems are communicating between them (wired or wireless (including radio) networks). This impact can be summarized as: o Wired communication costs: § Civil engineering works (cable paths). § Cabling (cable laying). o Wireless communication costs: § Site engineering works. § Civil works (installation).
· Power supply and power sources: It is defined as how systems are powered for its correct functioning and its correspondent power consumption. This impact can be summarized as: o Power grids (centralized energy concept) costs: § Civil engineering works (cable paths). § Cabling (cable laying). o Energy harvesting (considering future decentralized systems) costs: § Site engineering works. § Energy harvesting systems. o Energy efficiency costs.
GA 730640 Page 23 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
o Energy storage costs. o OC and WO power consumption costs.
· Research and Development (R&D): It is defined as how the system is improved along the time by investment in R&D by Infrastructure Manager, Equipment Provider and Stake Holders such as: o Information on the new railways services to be adopted next years. o X2RAIL1-WP3 Adaptable Communication System (ACS). o X2RAIL1-WP8 Cyber security. o FRMCS (Future Railway Mobile Communication System). o Predictive Maintenance. o Energy Harvesting Solutions. o Wireless communication. In the other hand it will be considered next topics that will help to deduce the saving costs that could be possible to obtain by installing SWOC instead OC, even to substitute actual OC and install one SWOC:
· OC and WO density: It is defined as how many devices are installed in a certain zone, considering that as many as elements are installed, deployment costs is increased but taking into account that some civil works can be shared for several OC or WO: o Amount of OC. o Amount of WO.
· Distances: It is defined as the distance between different objects: o Distance between OC and interlocking (for communication cabling). o Distance between OC and power sources (for power cabling). o Distance between WO and OC (for communication and/or power cabling). o Distance between WO and power sources (for power cabling).
5.3. Representative scenarios
In this chapter, the representative railway scenarios are described including all the associated topics and attributes identified in previous chapters. Each scenario is firstly described in terms of usage, scope and main characteristics of the scenario. Later on It is included its main attributes regarding density and distances identified into the topics of the Analysis, mainly focused on Density and Distances that is the main aspect to take into account in the economic analysis.
GA 730640 Page 24 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Each Railway network is based on a set of WO that are connected to an OC that is acting as an interface between those WO and the connected Interlocking. Usually the OC is considered as an Input/Output extension of the IXL, not providing any other extra capability to the system than transferring WO status to the IXL (by monitoring correspondent Inputs) and IXL commands to the WO (by activating correspondent outputs). One OC can be connected to one or several WO and connection between OC and IXL can be done through a dedicated wire or more complex wiring configuration. The predominant four railway transport categories are Mainline/High-Speed Rail, Urban/Metro, Regional Rail and Secondary Rail. Based on these four categories, different end user requirements in terms of Object Controller (OC) and connected Wayside Object (WO) density and distances can be identified. Apart of these four categories, it can be defined another one that is common for all of them: Station and Yard. This one is necessary to be taken into account in order to determining the installed OC and WO density. In all cases, an analysis approach can be considered taking into account Power Sources availability and distances between Power Sources and OC/WO. The same approach can be considered for Communication distances between OC and Interlocking and connections between OC and WO. It must be noted that density of WO and OC depends on signalling installation (amount of WO) and distance between them and the IXL. For instance it could be considered following types of WO to be managed:
· Signals.
· Track circuit.
· Point Machines.
· Others (gauge detector, intrusion detection,…)
5.3.1. Mainline/High-Speed Rail
Mainline is a track that is used for a high variety of trains and often it is the principal artery of the system from which branch lines, yards and sidings are connected. Generally it refers to a route between towns, as opposed to a route providing suburban or metro services. For capacity reasons, main lines in many countries have at least a double track and often contain multiple parallel tracks. Main line tracks are typically operated at higher speeds than branch lines and are generally built and maintained to a higher standard than yards and branch lines.
GA 730640 Page 25 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Mainlines may also be operated under shared access by a number of railway companies. Nowadays, interoperability in this kind of lines is achieved; although still have a lagging in technology and performance. High-speed Rail is a type of rail transport that operates significantly faster than traditional rail traffic, using an integrated system of specialized rolling stock and dedicated tracks. While there is no single standard that applies worldwide, new lines in excess of 250 km/h and existing lines in excess of 200 km/h are widely considered to be high-speed, with some extending the definition to include much lower speeds (e.g. 160 km/h) in areas for which these speeds still represent significant improvements. Given the high speeds of the rolling stock circulating along these lines, the traffic control and signalling system must guarantee maximum safety and reliability. In this lines It is considered a high availability of signalling system as well as not so high amount of signalling elements between station. It could be considered next OC and WO density for different elements:
OC/WO Density OC Low Signal Low Track Circuit Low Point Machine Very low Level Crossing Very low Related with Communication between OC and IXL and power grid from power sources to OC and WO It is considered long distances between them.
5.3.2. Urban / Metro
Rapid Transit Railways, including Urban and Suburban Rail, are a type of high-capacity public transport generally found in urban/suburban areas (Heavy/Light Metro, Subway and Tube). Rapid transit systems are electric railways that operate on an exclusive right- of-way, which cannot be accessed by pedestrians or other vehicles of any sort, and which is often grade separated in tunnels or on elevated railways. Services on rapid transit systems are provided on lines between stations typically using electric multiple units on rail tracks, although some systems use guided rubber tyres, magnetic levitation, or monorail. Due to the very nature of this type of lines, it is usual that they have a proprietary high-performance traffic control and signalling system (not fully standardized). In this lines It is considered a high availability of signalling system as well as not so high amount of signalling elements between station. It could be considered next OC and WO density for different elements:
GA 730640 Page 26 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
OC/WO Density OC Medium Signal Medium Track Circuit Low Point Machine Very low Related with Communication between OC and IXL and power grid from power sources to OC and WO It is considered medium distances between them
5.3.3. Regional Rail
Regional Rail also known as local trains and stopping trains are passenger (and in some cases also used for freight) rail services that operate between towns and cities but a lower speed than Mainline. These trains operate with more stops over shorter distances than Mainline rail, but fewer stops and faster service than Urban. Regional Rail services operates beyond the limits of urban areas, and either connects similarly-sized smaller cities and towns, or cities and surrounding towns. Regional Rail normally operates with an even service load throughout the day, although slightly increased services may be provided during rush-hour. The service is less oriented around bringing commuters to the urban centres, although this may generate part of the traffic on some systems. Other Regional Rail services operate between two large urban areas but make many intermediate stops. Regional lines sharing most of the requirements for mainline, but the OC and WO density is higher because the lower speed and the increase of shorter track circuits. Depending on the isolated region, previous sentence cannot be considered fully real, because in some cases there’s no signalling in the lineside so there’s no OC or WO. In this lines It is considered a medium availability of signalling system as well as not so high amount of signalling elements between station. It could be considered next OC and WO density for different elements:
OC/WO Density OC Low Signal Low Track Circuit Low Point Machine Very low Level Crossing Medium Related with Communication between OC and IXL and power grid from power sources to OC and WO It is considered long distances between them.
GA 730640 Page 27 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 5.3.4. Secondary Rail
Secondary Rail is a type of low traffic rail for the connection of long separated cities. It is normally used for the transport of passengers or goods over long distances usually between too far regions, crossing geographically harsh environments. The vast majority of the secondary rail lines around the world is often composes by single-track lines with medium or low traffic density and long headways between trains. The lack of cost effective modern technology means that many of these routes still have outdated safety systems, and/or manual operation. There are two kinds of secondary rail: Secondary Freight Rail and Secondary Passenger Rail. In these lines It is considered a low availability of signalling system as well as not so high amount of signalling elements between stations (even no available signalling between stations). It could be considered next OC and WO density for different elements:
OC/WO Density OC Very low Signal Very low Track Circuit Very low Point Machine Very low Level Crossing Very low Related with Communication between OC and IXL and power grid from power sources to OC and WO It is considered long distances between them.
5.3.5. Station & Yard
A station is defined as a railway location where a passenger train can start, stop or end. A yard is defined as an arrangement of tracks, other than main tracks, used for making up trains (shunting), storing cars, trains and other purposes. Depending on the Station or Yard size it can be considered the WO and OC density from low (small stations or stopping areas between station) to very high (in case of main stations into cities and big depot zones) In this station It is considered a high availability of signalling system. It could be considered next OC and WO density for different elements:
GA 730640 Page 28 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
OC/WO Density OC High Signal High Track Circuit High Point Machine High Level Crossing Medium/Low Related with Communication between OC and IXL and power grid from power sources to OC and WO It is considered short distances between them
5.4. Factors involved (Railway Technology)
The technologies and factors involved in wayside traffic control equipment have implications when evaluating the different scenarios where the application of this proposal is reasonably advantageous. The adoption of one or several railway scenarios implies the use of a certain technology at the trackside that can impact the final result of the proposal. This chapter evaluates the different options currently available, analysing the advantages and disadvantages of each one, focused in Power, Communication and Diagnosis and Maintenance improvement. There’s lot of possibilities considering the involved technological factor but it can be considered factors indicated in next chapters.
5.4.1. Type of WO
Technological factors related with WO is mainly based on how the WO is powered and how the WO is managed (activating, monitoring,…) from the OC. Depending on the type of WO the used technology will imply different solutions. It can be considered next possible solutions for the WO:
· Powered from the OC. Those WO that are directly powered from any OC output that provides the energy to the correspondent WO: o Light Signals (LED, Bubble,…) o Point Machine (380 V AC, 110 V DC,…) o Train Detection System (Track Circuit, Axle Counter,…) o …
· Not powered from the OC: Those WO which power is activating through an external power source but managed by any digital output or by a logical connection between the OC and the WO: o Direct digital activation. o Digital communication for activation.
GA 730640 Page 29 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
In both cases first SWOC improvement will be based on:
· Reducing length of power cabling between power source and OC and WO.
· Reducing length of communication cabling between IXL and OC.
5.4.2. Communication
Technological factors related with communication between OC and IXL (or any other external system) are mainly based on how the OC is physically connected to the control source. Traditional communication media is based on wired communication that can use cupper wires or fibre optic wires. This type of communication implies several works for laying cables (civil works, cable deployment, cable connections,…) that depends on the distances between elements. This also can apply to communication between OC and WO (in case of digital communication), but including power cabling to the media used for connecting both systems. Also It is made a distinction between three different concept solutions as “Centralized and Wired solution”, “Distributed and wired solution” and “Distributed and wireless solution” (considering that centralized and distributed are related with the OC’s physical distribution):
· Centralized and wired solutions is the state-of-the-art in OC systems. OCs are centralized with each interlocking system and wired in a point to point configuration, generally with redundant path, with WO (track circuits, point machines, etc.). This solution involves a long wired infrastructure as well as civil works for laying cabling.
· Distributed and wired solutions is less common than the state-of-the-art in OC systems but widely adopted by suppliers. OCs are distributed with each interlocking system and wired in point to multipoint configuration, generally with redundant path, with WO (track circuits, point machines, etc.). This solution involves a long wired infrastructure as well as civil works for laying cabling.
· Distributed and wireless solution involves that OCs are connected to the interlocking by wireless communication, which involves a wayside cable and civil works reduction.
GA 730640 Page 30 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Another possible concept solution would be a mix between distributed solution (in terms of power supply) and wired network approach, only when the network cabling is already available due to the use of the installed network infrastructure. It is needed to note that in case of wireless solution where the a high density of OC and WO is installed, there’s a risk regarding interferences between wireless channels that could generate transmission errors and reduce the quality of service and availability of the system. It is needed to take this into account in these cases as a frequency analysis and planning for all the elements will be needed.
5.4.3. Power
Traditional power methods for OC and WO are based on connecting those elements to the power grid laid down along the track specifically deployed for powering those elements. This approach implies several works such as:
· Civil works for preparing the yard for laying down the cables, including pipes and manholes.
· Cable laying, connections, joints, isolation,…
· Specific cable protection from external elements (animals, environment, vandalism…) and cable theft.
· Powering itself, including power storage and continuous power provision. OC are typically powered through the power grid deployed in all the railway network. Usually the power is done through redundant lines by using different sources for powering an Uninterruptible Power Supply (UPS) that is connected to the correspondent OC, in such way that the power availability is constantly assured by the use of redundant lines and the use of UPS. WO can be powered directly through the power grid deployed in all the railway network and activated by the OC or can be powered directly from the OC. How WO is powered depends on:
· WO type.
· Power needed for feeding the WO.
GA 730640 Page 31 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 5.4.4. Diagnosis and Maintenance
Current status of OC and WO diagnosis and maintenance is based on statistical values about equipment availability, as Mean Time Between Failures (MTBF) and Medium Time To Repair (MTTR). With those values, preventive maintenance is established as periodic works to be performed in the equipment and substituting/updating parts of the equipment although the old component is still valid for the equipment purpose. This generates that some parts are just substituted because according to the statistics is needed to do, but not taking into account the real state of the component. In the other hand, current information provided by the OC to the maintainers is not enough for helping to maintainer to reduce reparation time, that suppose a time consumption (and the associated costs) for finding the problem and for fixing it. New Diagnosis and Maintenance systems have been designed in order to give information that is more accurate to the maintainers who will determine the necessity of a maintenance (e.g. monitoring the cable resistance and raising an alarm when this resistance is reduced, instead periodically substitute the cable because the resistance could be reduced).
5.5. Proposed scenario
The main objective of this section is to determine the most convenient scenario where the proposal is a priori (with the available data) approachable in technical and economic terms. The most suitable scenario could be those that contains several OC and WO and distances between them and between OC and IXL is longest, but taking into account other aspects (technical and installation aspects) for determining the proposed scenario. Considering the scenarios listed in chapter Fehler! Verweisquelle konnte nicht gefunden werden. Fehler! Verweisquelle konnte nicht gefunden werden., and not taking into account Station and Yards as this scenario was listed as common for all other scenarios and the selected scenario includes Station and Yards, we can argue for each one next items for selecting or not selecting it:
· Mainline/High-Speed Rail. Applying the Smart Wayside Object Controller solution to this scenario (with fixed block technology) could improve economic terms by savings on wired installations along the track. New Mainline/high-speed lines are based on new standards already deployed and installed in the track, such as virtual signalling and moving blocks that reduce the number of installed WO in the track up to the minimum. In this cases it could GA 730640 Page 32 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
be considered the possibility to use SWOC for those minimum WO to be installed, but taking into account that there’s no so much WO it can be assured this scenario is not the best for determining the cost saving. Even with these advantages, it is necessary to analyse whether the expected savings covers the necessary costs for its development, deployment and maintenance with sufficient margin, so that it is a viable scenario for the proposed solution against the ERTMS L3 solution. Taking into account that new technology will provide of moving blocks and virtual signalling for trains, this will reduce the amount of OC and WO to be installed to the minimum, so that this scenario can be considered as no candidate.
· Urban/Metro. This scenario is not a suitable candidate, given the environment where this type of transport is used. This type of transport is generally located in urban areas with a high population index where it is very affordable to adopt wired communication solutions due to existing urban /sub-urban civil infrastructures. In addition, the average length of the lines (about 50 km), added to the fact that CBTC systems usually used reduce the quantity of OC and WO for traffic control, does not benefit a priori from the savings gained by replacing the wayside wired communications with wireless communications. Similarly, low power supply areas and power consumptions factors does not contribute to adding value to this scenario, given that in the urban / suburban environment these factors have no impact. In the other hand, wireless communication are affected by possible interferences because the population concentration and number or wireless devices using the same frequency spectrum that could saturate the communication channels and generate interferences in communication and creating communication loss.
· Regional Rail. This scenario is the most suitable candidate for using SWOC, taking into account this scenario as a high/medium OC/WO density, with fixed blocks, vertical signalling, medium distances between stations and low accessibility for some locations. It can be suppose that installation of wireless SWOC powered by Energy Harvesting will save installation costs and will improve maintenance tasks. Improvement in this type of scenario are:
o Complexity of the track due to the topology of the line and the number of remote OC
GA 730640 Page 33 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
o Wireless SWOC can be easily deployed in existing or new lines as communication cabling works are avoided.
o Distributed SWOC architecture based on wireless communication can create a communication mesh in those lines that will allow all SWOC (and its connected WO) to be accessible from IXL.
o Energy Harvesting implementation in remote zones will avoid civil works as well as reduce illegal actions related with power sources (stolen cables, illegal connections,…)
o Scheduled maintenance forces to spend time (and money) in trips to places for performing maintenance tasks that could be executed remotely.
· Secondary Rail: This scenario is not a suitable candidate, considering the usage of this type or railway by the IM. This type of scenario is generally connecting distant locations but the usage of the network is very low and doesn’t require a high availability of the system. It could be a candidate because the distance between OC/WO to the power and communication “provider”, but as there’s no so many elements as well as the situation that there’s no new Secondary Rail under construction (just maintenance), there’s no necessary to check it.
5.6. Analysis of economic models
Once the scenario to be considered is selected (Regional lines as it was indicated in previous chapter), the analysis will be focused in the estimated percentage economic impact of using SWOC (wireless, distributed concept, Energy Harvesting usage,…) in comparison to the actual available OC (wired, centralized concept, energy grid) taking into account next concepts:
· Feasibility of Smart Wayside Object Controller
· Centralized and wired solutions vs Distributed and wireless solutions.
· Diagnosis and Maintenance.
· OC/SWOC Power. As It is difficult to establish a clear comparison in terms of cost (money) between OC vs SWOC because it depends on several factors such as: country, environmental weather, national rules for installation, private/public investment,…, the analysis will be based on works and material saving from actual OC to SWOC.
GA 730640 Page 34 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 5.6.1. Feasibility of SWOC
As it was indicated in previous chapter, first concept to take into account is the Feasibility of Smart Wayside Object Controller. Actual OC is based on Input/Output extension of IXL without any other advance. This OC is connected to the IXL through a copper or fibre optic cable that is dedicated to the OC connection (although in some cases It is used a derivation of the cable for using same civil work and cable for several OC). This OC concept is based on old technologies that doesn’t allow the implementation of Smart devices as an extension of IXL. For this reason the OC can be considered a basic extension of the IXL. SWOC will be based on enhanced OC that will provide to IXL, and other external systems, new capabilities that require company’s investment on hardware and development. Such capabilities are considered mainly in enhanced communication (mainly wireless communication), power consumption optimization and advanced diagnostic and maintenance capability. It is important to note that last technological progress around the world such as wireless communication and energy harvesting has not been used in railway systems because safety, security and development reasons (as it could be considered the idea of use the known system better than others that is not known). Into this technological progress it has been included others as computational capacity and size reduction that can offer a high capacity in low space for easily installation. Main advanced into the railway systems has been based on new system such as ERTMS, CBTC and others, but not in traditional systems that still are based on OC as an extension of the Interlocking’s I/O. Considering previous paragraph and possible SWOC improvement, it can be considered that next capabilities can be achieved with actual technologies and cheap hardware without expensive investment:
· Wireless communication: o New communication hardware and application are increasing speeds (up to 10Gb/s in 5G communications) and covered distances between connected systems. o Communication systems offer redundant systems as well as routing capacity for assuring connection between network components. o WiFi is broadly used in the industry and the needed hardware for covering large places is fully successfully implemented and installed without big investment.
· Energy Harvesting.
GA 730640 Page 35 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
o Depending on the selected Energy Harvesting system, the costs for deployment can be compensated just after the installation (e.g. low consumption systems powered by solar modules) or after several years (e.g. wind turbines). o In case of more optimal energy harvesting system is developed, it could be easily installed near SWOC or WO by substituting already installed energy harvesting. This suppose a reduction of the new installation to the minimum (e.g. more efficient solar panel for substituting installed one), that become into an important cost reduction.
· Diagnosis and Maintenance: o Technologies as machine learning, artificial intelligence, augmented reality and data gathering techniques, widely used in the industry, are accessible for developing new functionalities into small and smart systems as it considered the SWOC. o Implementing this functionalities into new platforms is considered cheap as there’s lot of open sources that provide the diagnosis and maintenance capabilities to be used.
· Equipment. o Reduction of hardware costs and the use of development kit and platform, including communication modules, I/O modules, embedded sensors as well other modules for increasing capacity of the module, are generating the easy implementation of new functionalities and services into the hardware by updating hardware firmware and/or software updates. o Despite of costs for developing SWOC by implementing new hardware, firmware and software that could be considered as high costs, new development techniques and Agile methodologies reduce those costs and time-to-market time in such way that the effort is even lower than the effort for implementing actual OC.
· Reliability, Availability, Maintainability and Safety (RAMS) o RAMS values assures by new technologies offer to the system implementation a high added value for SWOC development that is similar (even higher) than actual OC. In the other hand, most of the company’s R&D costs investment happens while seeking new knowledge for totally new system. Considering that, in opposite of uncertain success of the new system implementation, SWOC could be considered as an improvement of existent system (such as “interlocking size reduction” or as OC equipped
GA 730640 Page 36 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models with intelligence), this new needed knowledge is already available in main railway companies but not used in railway systems. Taking into account that the scope of SWOC is focused on a specific and directed objective, investment in R&D can be considered as “Applied Research” that aims to address a specific industry need. This type of investigation are focused on specific commercial objectives regarding products or process, so the company’s profit is considered returned to the company in short terms that allow a future costs reduction in short terms. Considering above paragraphs it can be considered that cost of SWOC could be a little bit bigger than OC but will provide several other capabilities to the OPEX that could compensate the difference after short period of time.
5.6.2. Centralized & wired solutions vs Distributed & wireless solutions.
As it was described in chapter 5.4.2 there’s three different concept solutions in terms of communication concept: Centralized and Wired solution, Distributed and wired solution and Distributed and wireless solution. Actual systems are based on Centralized or Distributed but Wired solution, that means that from the main system (typically the interlocking) all the OC are controlled and managed in such way that there’s a point to point or point to multipoint connection between the IXL and each OC. This generates the need to use a cable between the IXL and the OC (point to point). Although it can be used the same cable core but different internal cables for connecting several OC (point to point). In some cases It is used the same cable and the same wire for the connection by creating point to point structure. In all that cases, It is needed to perform civil works for the cabling path as well as deploy the cable itself and the correspondent join and derivation works. Costs of this works depends on the country, rules, cupper market price, … but It is one of the most important cost in the OC deployment. New systems are based in Distributed and wireless communication solutions that obviously can suppose a big cost saving because works for cabling paths, cabling laid and others are no longer needed. Works for civil works for hosting OC and SWOC are similar and can be considered as the same cost, so there’s no extra cost saving in this case. Depending on the wireless communication solutions it could be needed to invest in other infrastructure, but as it was indicated into chapter 5.6.1, it has been demonstrate that WiFi deployment is feasible in big areas without big investment. Even more, it can be used actual communication network (such as GSM-R, 3G and 4G mobile netwoks) for
GA 730640 Page 37 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models using as the communication platform, this mean that the cost is reduced to the use of such networks (usually IM has already installed GSM-R systems that are covering the whole railway topology). Considering above paragraphs, it can be considered that in case of Distributed Architecture (even Centralized but wireless systems) the costs saving is enough for covering the extra cost that it could suppose the use of SWOC instead OC.
5.6.1. OC/SWOC Power
Current OC system power management is not available, because the simple OC implementation of the WO connected to Power sources. This does not allow taking advantage of new technologies for implementing energy efficiency usage as power consumption reduction because sleeping mode or standby mode that could be activated when the WO is considered not to be used because not scheduled trains. As well as the indicated Power Source management, current OC and WO are powered from the power grid, not considering the possibility to the use of Energy Harvesting solutions that can be installed in a specific site, near the equipment to be powered. This current solution implies several civil works to be performed, as well as cabling laying (in a similar way as indicated for communicating cabling). The usage of Energy Harvesting system are broadly used in the world, so it can be considered those product with the enough mature state that can assure the power availability. In any case, and depending on the WO to be powered (mainly taking into account Point Machines objects), the Energy Harvesting cannot be enough to be used and it could be needed to use another technique or system. The system to be used cannot be analysed until the whole picture of a specific and detailed scenario is not defined. In terms of CAPEX costs related with powering OC and WO, apart of the power consumption during operation, are related with civil works for cabling laying, as well as cable itself. Considering OPEX costs, there’s another important cost that must be considered: cabling thefts that during last time it has became in an important cost during OPEX activities. Those costs implies costs for restoring civil works and cabling restitution.
5.6.2. Diagnosis and Maintenance
Current OC doesn’t implement any advanced Diagnosis capability and Maintenance is based on preventive maintenance that force to substitute some parts from the OC because the average time of use is reached.
GA 730640 Page 38 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
SWOC advanced Diagnosis will support that from Maintenance Staff more accurate information is received that will help for performing Maintenance works taking into account the provided information regarding elements that are failing or their performance is reduced because any malfunctioning. Maintenance capability will provide detailed information about the SWOC that will avoid scheduled works that will generate not necessary costs such as trips for resetting the equipment. Current works for Diagnosis and Maintenance are based on:
· Preventive maintenance according to calculated expected life of the components of the system. o This generates costs because replacement of components that still could be work for several time without problems. o This generates costs because replaced components are used as spare parts in case of need, but not being sure the component will work while the final component is installed.
· Corrective maintenance according to staff expertise where there’s no information about module could be failing. o This generates costs because looking for malfunctioning component can spend lot of human factor time. Comparing with actual (OC) and Diagnosis and Maintenance costs, SWOC will reduce costs to the minimum because:
· Predictive maintenance based on condition monitoring will be based on accurate information reported by SWOC to the Maintenance system that will allow substitution of elements that the real expected life of the component is near the end. o This generates a high costs reduction by substituting just the components that could fail, taking into account specific information about the component. o This generates a high costs reduction by scheduling maintenance according to specific situations and components in equipment that really need to be substituted.
· Corrective maintenance will be based on detailed diagnosis information from the SWOC: o This generates a high costs reduction by using the provided information from the SWOC diagnosis system about the module or component that is failing.
GA 730640 Page 39 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 5.7. Result of the analysis
As conclusion of the analysis performed above, the use of SWOC in Regional lines can suppose the most significant costs saving, mainly for new lines as well as for updating some OC with new SWOC. Taking into account that the main OC CAPEX cost is for civil works and cabling, the use of wireless SWOC connected to a local Energy Harvesting system should be an advantage in economic terms. For OPEX costs, the use of predictive maintenance by developing an advanced Diagnosis and Maintenance embedded software suppose a costs reduction in terms of corrective rostering staff and preventive maintenance. As SWOC will offer more accurate information related with Diagnosis, the staff that is in charge of corrective maintenance will be able to solve system problems faster than before. This will reduce costs for not operation during not availability of the system as the malfunction equipment or module can be faster identified by the staff and substitute. With the possibility of remote operation of SWOC, maintenance staff will be able to perform diagnosis and maintenance tasks in a more efficient way, that will reduce labour costs In the other hand, there’s another cost related with cabling theft. This cabling theft generates OPEX costs for restoring civil works, cabling and for not availability of the system while the cabling is restored. For this reason, this cost can be considered reduced to very low cost. As a summary, next table (Table 2 OC vs SWOC compared costs) contains the compared costs between OC and SWOC for the different topics and items analyses in this chapter.
GA 730640 Page 40 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Costs Analyses Item Specific Item Works/Tasks Comments OC SWOC Civil Works High Low OC and SWOC installation itelf can be considered CAPEX the same cost, but not the civil works for cabling Cabling High Low paths as well as the cable itself Installation FAT Medium Medium Performing tests (FAT, SAT and Commissioning) Tests SAT Medium Medium costs is considered the same for both (OC and Commissioning Medium Medium SWOC) Preventive Preventive maintenance in SWOC is expected to be High Medium Material (spare parts, Maintenance reduced because implementation of enhanced cable,…) Corrective Diagnosis and Maintenance capabilities into Medium Medium Maintenance SWOC. Software and Remote Software and Firmware updates reduces Diagnosis and Update costs Firmware High Low traveling costs, as well It is not an usual work to be Maintenance updates performed with high frequency. OPEX Task forces for Preventive maintenance in SWOC is expected to be preventive Medium Low reduced because implementation of enhanced maintenance Diagnosis and Maintenance capabilities into SWOC Human Staff costs Staff rostering for corrective Medium Medium maintenance Civil engineering High Low Wired works Communication Cable High Low System Site engineering N/A Medium Wireless works Civil works N/A Low
GA 730640 Page 41 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Costs Analyses Item Specific Item Works/Tasks Comments OC SWOC Civil engineering High N/A Considering Energy Harvesting implementation in Power grids works SWOC deployment Considering Energy Harvesting implementation in Cable High N/A SWOC deployment Civil engineering N/A Medium Including works for short cables for SWOC Power Supply works connecting SWOC with power sources Energy Harvesting and Power Energy It is considered out of the SWOC scope the sources Harvesting N/A Medium implementation of Energy Harvesting, but not the system ussage. Energy Efficency N/A Low OC doesn’t allow the efficient use of energy It is considered out of the SWOC scope the Energy Storage N/A Medium implementation of Energy Storage, but not the ussage of the stored energy. WO consumption can be reduced from SWOC by OC and WO power consumption Medium/High Medium/Low implementing energy saving techniques into SWOC New railways services N/A TBD New services scope is To Be Defined (TBD) as well X2RAIL1-WP3 (Adaptable as the rest of new implementations expected by N/A TBD Communication System) the Railway business, but its implementation could FRMCS (Future Railway Mobile be better supported by SWOC than by actual OC R&D N/A TBD Communication System) Predictive Maintenance N/A TBD Energy Harvesting solutions N/A TBD Wireless communication N/A TBD
Table 2 OC vs SWOC compared costs
GA 730640 Page 42 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
As an example about cost reduction and benefits we could consider scenario shown below, where it is possible to understand the cost reduction of using SWOC instead OC:
· OC scenario (Figure 1 OC Centralized and Wired solution) is based on a cross zone into a regional line, where Interlocking is installed into main station, at about 55 km from the cross.
Power Line Data Line
300 m
300 m 50 m 50 m 550 m OC 520 m IXL 55000 m
Figure 1 OC Centralized and Wired solution
· SWOC proposed scenario (Figure 2 SWOC Distributed and Wireless solution) is based on a cross zone into a regional line, where Interlocking is installed into main station, at about 55 km from the cross, Energy Harvesting system is installed in the cross zone and communication between Interlocking and SWOCs is made through public 4G network.
SWOC SWOC 10 m
Power Line 20 m 300 m Data Line 50 m 50 m
30 m
30 m
500 m SWOC IXL 55000 m
Energy Harvesting
GA 730640 Page 43 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Figure 2 SWOC Distributed and Wireless solution
Next table contains an estimation of costs obtained with the application of Table 2 OC vs SWOC compared costs to the mentioned scenarios.
GA 730640 Page 44 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Specific Costs Analyses Item Works/Tasks Comments Item OC SWOC 990m: · 30 m 56770m: · 30 m · 55000 m · 500 m · 300 m · 50 m · 300 m · 50 m · 50 m · 10 m Civil Works · 50 m · 20 m · 520 m · 300 m · 550 m 3 SWOC Civil works for SWOC is clearly reduced, but cost is increased CAPEX 1 OC because Energy Harvesting system to be installed, as well as the Energy Harvesting system basement and equipment itself Installation (including basement) 990m: 56770m: · 30 m · 55000 m · 30 m · 300 m · 500 m · 300 m Cabling · 50 m · 50 m · 50 m · 50 m · 10 m · 520 m · 20 m · 550 m · 300 m FAT Performing tests (FAT, SAT and Commissioning) costs is Tests SAT considered the same for both (OC and SWOC) Commissioning Preventive 4 times per Diagnosis and Material 1 or 2 times per year Maintenance year Maintenance (spare parts, According to Information provided by SWOC Corrective OPEX cable,…) When needed When needed Maintenance
GA 730640 Page 45 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Specific Costs Analyses Item Works/Tasks Comments Item OC SWOC Software and SWOC can be remotely updated, so costs are reduced because Update costs High Low Firmware updates displacement to the site Task forces for 4 times per According to Information provided by SWOC, preventive works preventive 1 or 2 times per year year are reduced Human Staff maintenance costs Staff rostering for corrective maintenance Civil engineering 55000 m 0 Wired works Communication Cable 55000 m 0 System Site engineering N/A 3 x SWOC Wireless works Civil works N/A 3 x SWOC basement 56770m: · 55000 m · 300 m Civil engineering · 300 m N/A works · 50 m · 50 m · 520 m Power Supply · 550 m and Power Power grids 56770m: sources · 55000 m · 300 m · 300 m Cable N/A · 50 m · 50 m · 520 m · 550 m
GA 730640 Page 46 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Specific Costs Analyses Item Works/Tasks Comments Item OC SWOC Civil engineering N/A 1 x Energy Harvesting System Energy works Harvesting Energy Harvesting N/A 1 x Energy Harvesting System system Energy Efficency It is not possible to estimate the reduction of power N/A Low consumption because several factors will be involved (rail traffic, rules for saving power,…) 1 Battery pack according to Energy Storage N/A estimated power conssumption Main difference is the optimization of the power consumption OC and WO power consumption Medium/High Medium/Low according to implemented energy efficiency. New railways services N/A TBD X2RAIL1-WP3 (Adaptable N/A TBD Communication System) New services scope is To Be Defined (TBD) as well as the rest of FRMCS (Future Railway Mobile new implementations expected by the Railway business, but its R&D N/A TBD Communication System) implementation could be better supported by SWOC than by Predictive Maintenance N/A TBD actual OC Energy Harvesting solutions N/A TBD Wireless communication N/A TBD
Table 3 Estimated costs OC vs SWOC in a possible scenario
GA 730640 Page 47 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
6. Analysis of the state-of-the-art of the wireless communication technologies
6.1. Purpose and scope
The purpose of this chapter is to form a basis for exploring and developing technical means using radio communication technologies in order to enable wireless communication between trackside signalling control subsystems, like interlocking cores etc., and Smart Wayside Object Controllers (SWOC) or even field elements. The scope of the chapter embraces following areas: type of wireless technology including its characteristics, type of technology operator and necessary requirements for practical use and deployment.
6.2. Objectives
The aims of this chapter are to:
· Identify available wireless technologies
· Characterize them from the point of view of performance and general applicability
· Describe their advantages and disadvantages for SWOC application.
Based on the analysis1 part the main goal is to propose the candidates from the listed wireless technologies which are suitable to be used in specific Smart Wayside Object Controllers (SWOC). And when selected, the second goal is to identify the means and processes necessary to successfully apply them for the mentioned purpose.
1 In the analysis predominately technical characteristics are taken into account and economic criteria have only minor influence. X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 6.3. Wireless communications technologies
6.3.1. Advantages & Disadvantages of Wireless Networks
This paragraph compares conventional wired/cable connections of devices versus wireless connections. Their advantages and disadvantages are listed below.
Process phase or Cable connection Wireless connection quality
design precise reconnaissance and surveying reconnaissance and surveying easy necessary for point-to-point links, complex for networks constructional and earthwork design necessary mathematical modelling of propagation of the classical drawing of the whole line electromagnetic waves between between the end points the end points
if line of sight is free no modelling only drawing of both radio transceivers/antennas at both end points fairly easy design if using external network provider, complex design for a proprietary network
installation highly laborious earthwork easy (for technologies requiring LOS where it is not available may be fairly laborious)
change difficult fairly easy if propagation of the electromagnetic waves is not obstructed
maintenance easy fairly laborious
reliability high medium
GA 730640 Page 49 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Process phase or Cable connection Wireless connection quality
immunity against immune, depends on level of isolation sensitive for radio transceivers lightning
galvanic isolation usually 4KV isolators used no galvanic isolation necessary systems
immunity against internal cable crosstalk on the long cable depends on area confluence interference depends on spectrum external cable crosstalk from catenary management and high-voltage lines depends on quality (and allowed dimensions) of antennas
Life-cycle cost (LCC) very high cost of ground works, medium low cost of installation, minor to cost of cables medium cost of terminals
power consumption low low to medium
bandwidth medium for metallic twisted pairs low to high – depends on selected technology high for coaxial cables
very high for optical cables
latency low low to high – depends on selected technology
transmitted data good – cryptographic protection usually low – cryptographic protection security unnecessary necessary
line dependability low to good – depends on installation high for the line itself – nothing to technology, type of cable steal
good for the transceivers – not very attractive for thieves low in regard to interference
Table 6.1 – Comparison of cable and wireless connection
GA 730640 Page 50 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 6.3.2. Available terrestrial wireless technologies
In the following paragraphs available standardized wireless technologies are described in detail2. Only those which could suffice to the expected requirements are characterized in higher detail. Technologies like IRDA, RFID or UWB are shown only in the graph for reference.
6.3.2.1. Communications protocols The ISO/OSI layered communication protocol model defines seven protocol layers. But often different specifications providers/owners, like standards bodies (ISO, ITU, ETSI, IEEE, IEC), develop only a subset of these layers:
· physical layer (PHY)
· link layer – often mentioned as media access control (MAC) layer
Many wireless technologies are then often developed by industrial consortia, and add only some necessary higher communication layers, like:
· network layer
· application layer
More sophisticated protocol stacks might use other layers of the ISO/OSI layered model adding more layers between the network and application layer:
· transport layer
· session layer
· presentation layer
But mostly the functions of these latter layers are embedded in fewer layers which are then named according the rules of the specification owners.
6.3.2.2. Communications application areas In order to do a valuable analysis it is useful to understand what are the application areas, what are the Use cases. The main application areas for data transmission are:
2 Future technology advancement could change the current picture.
GA 730640 Page 51 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· office and home networking
· metropolitan networking
· country-wide and international networking
· industrial control networking
· monitoring and measurement data acquisition
· Intelligent Transportation Systems – ITS
· Internet of Things – IoT
6.3.2.3. Evolution of terrestrial networks Classical terrestrial networks are composed of a transit core network as a fixed backbone, and of a set of capillaries to connect the terminals. Capillaries may be individual or shared between local users. Wireless terrestrial networks are using radio technologies (or sometimes light wave technologies) for the capillaries. Capillaries may cover a distance range from 10 meters to 30 km, depending on the technologies and on the required performances. The basic interest of wireless connections is the ability to manage nomadic or mobile access. Nomadic means moving from place to place, with the link interrupted between. Mobile means moving continuously while keeping the link alive. The main standards and their historical evolutions are presented in Figure 6.1. It can be seen as a “hill” with 2 slopes. the right slope is devoted to cellular radiophone networks provided by Telecom Operators (ILEC or CLEC) with successive generations (2G, 3G, 4G); the left slope is devoted to data processing and computer networks, named WxAN (Wireless x Area Networks). The x is related to the surface coverage, which can be very small (x = P, for Personal), moderate (x = L, for Local), intermediate (x = M, for Metropolitan) or large (x = W, for Wide).
GA 730640 Page 52 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Transit core network Transit network IP based (v4 ® v6) ATM / SDH 1 Gb/s optical, asynch STM1 to16 optical, synchronous Peripheral transit network may be wireless (WMAN) 802.16 WIMAX-HIPERACCESS
Hot Spots WWAN WPAN 4G cellular WLAN LTE 3G cellular IMT 2000 / UMTS 2G cellular Wimedia 802.11a→p Cognitive GSM BT, Zigbee Wifi to Wave Radios 3G+ HSDPA UWB (ITS) 2G+ GPRS & EDGE WSN 5G Cellular Wireless capillaries Transit backbone capillaries Transit Wireless TETRA MOTEs, Dust TETRA 2
Figure 6.1 – Terrestrial Networks
The upper part shows the evolution of transport or transit networks, from circuit oriented synchronous technologies (SDH: Synchronous Data Hierarchy) for real-time digital voice, to packet oriented asynchronous technologies well adapted to data communication. “Transit” is preferred to “transport”, in order to avoid any confusion with OSI Transport Layer. With this evolution, the switching engine in the nodes became IP (Internet Protocol, based on long packets, and adaptive procedures), instead of ATM (Asynchronous Transfer Mode, based on very short packets, switched on the fly). The transmission links between nodes became Ethernet based, instead of STM based (Synchronous Transfer Mode multiplexing process). This global evolution brings simplicity and cost-effectiveness. Indeed, it was difficult to manage a fully synchronous backbone at a continental scale. The lower part shows the convergence at the top of the “hill”, between the 2 slopes: WxAN and cellular radiophone technologies. This lower part roughly covers Layer 1 (PHYsical), Layer 2 (Data Link) and adaptation layers to backbone upper protocols, as defined in the OSI Reference model. Voice traffic has been overpassed by data traffic since 2005 in major European countries, and then the 3G technical justification for CDMA became gradually invalid. CDMA was initially preferred to TDMA for voice service targeting: CDMA gives twice the capacity of TDMA only because voice usually includes 50% of silence! The convergence between WWAN and 4G Cellular is obtained with LTE (Long Term Evolution of Cellular) which is the current solution for 4G cellular networks. WWAN was pioneered by 802.20,
GA 730640 Page 53 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models an aborted IEEE standard. Then LTE has been preferred to mobile WIMAX (802.16e, going to 802.16m) which became too complex. WIMAX is still alive in fixed version (802.16d) at the edge of the backbone when cabling is too expensive (e.g. far from downtown). In parallel with the 2-4G Cellular slope and with the WxAN slope, there are similar evolutions respectively in Professional Mobile Radio (PMR) and in WSN (Wireless Sensor Networks) move:
· The convergence between Public, Private/Professional communication will be obtained by LTE based solution: there will be no TETRA 3 and LTE in low UHF is now expected to replace TETRA;
· WSN with MOTEs and “Smart Dust” are going out of WPAN (with ZIGBEE and UWB) to join “Internet of Things” world. The junction could be obtained with 4G, more probably with 5G.
Notice that LTE is the first Cellular network to be natively IP. Voice is only provided through IP as a packet switched service, like any alternative data flow, and priorities are managed by the IP capabilities:
· either Type of Services: ToS is a coded field in the header of IPv4, and its capability is limited;
· or Quality of Service: QoS is a fully integrated service of IPv6, with specific packets inserted into traffic.
Notice that managing ToS or QoS is feasible only if a minimum of quality control is offered by the vector to be used (at OSI layer 2). This is the case with LTE and G5, but in different respects . There is a basic set of standards for LTE, which is widespread via Telecom Operators. But a number of variants are being investigated to supply adjacent markets that have different needs. Multi- standard terminals can be expected through Software Defined Radio (SDR), which is a transversal technology officially encouraged by ECC. The emergence of 5G is expected beyond 2020. It is assumed to be backward compatible with LTE, but will include additional capabilities about multi-band and multi-radio subsystems. This can be done by SDR going to Cognitive and Pervasive Radio evolution. SDR is not the only transversal technology applicable to radio networks: multi-carrier OFDM (Orthogonal Frequency Division Multiplex) and multi-antenna processing (MIMO: Multiple Input Multiple Output) are also transversal technologies applicable to Digital Broadcast Radio, WLAN, WIMAX, and LTE. Furthermore, OFDM is applicable to SATCOM. Using OFDM increases the density of the channel (in bit/Hz), but also the susceptibility to Doppler effect.
GA 730640 Page 54 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
6.3.2.3.1. Data rate and ranges of wireless technologies The below figure, developed and drawn for the purpose of this analysis, shows the range of the wireless technologies in relation to the available data rates. Based on this figure the most appropriate technologies are then described in more detail.
Figure 6.2 – Terrestrial Networks
6.3.2.4. IEEE 802.11 family
6.3.2.4.1. IEEE 802.11a/b/g/n/ac (WiFi) This part has been taken and adapted from Wikipedia [3]. The WiFi standard is widely used public standard designed to enable predominantly office and home networking. It is focused to ensure high bandwidth, high data rate transmissions for the transport of long frames of data packets and files. IEEE 802.11 is a set of media access control (MAC) and physical layer (PHY) specifications for implementing wireless local area network (WLAN) computer communication in the 900 MHz and 2.4, 3.6, 5, and 60 GHz frequency bands. They are created and maintained by the Institute of Electrical and Electronics Engineers (IEEE) LAN/MAN Standards Committee (IEEE 802). The base version of the standard was released in 1997, and has had subsequent amendments. The standard and amendments provide the basis for wireless network products using the Wi-Fi brand. While each amendment is officially revoked when it is incorporated in the latest version of the standard,
GA 730640 Page 55 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models the corporate world tends to market to the revisions because they concisely denote capabilities of their products. As a result, in the marketplace, each revision tends to become its own standard. The 802.11 family consists of a series of half-duplex over-the-air modulation techniques that use the same basic protocol. 802.11-1997 was the first wireless networking standard in the family, but 802.11b was the first widely accepted one, followed by 802.11a, 802.11g, 802.11n, and 802.11ac. Other standards in the family (c–f, h, j) are service amendments that are used to extend the current scope of the existing standard, which may also include corrections to a previous specification. 802.11b and 802.11g use the 2.4 GHz ISM band (industrial, scientific and medical radio bands), operating in the United States under Part 15 of the U.S. Federal Communications Commission (FCC) Rules and Regulations. Because of this choice of frequency band, 802.11b and g equipment may occasionally suffer interference from microwave ovens, cordless telephones, and Bluetooth devices. 802.11b and 802.11g control their interference and susceptibility to interference by using direct-sequence spread spectrum (DSSS) and orthogonal frequency-division multiplexing (OFDM) signalling methods, respectively. 802.11a uses the 5 GHz U-NII band, which, for much of the world, offers at least 23 non-overlapping channels rather than the 2.4 GHz ISM frequency band offering only three non-overlapping channels, where other adjacent channels overlap—see list of WLAN channels. Better or worse performance with higher or lower frequencies (channels) may be realized, depending on the environment. 802.11n can use either the 2.4 GHz or the 5 GHz band; 802.11ac uses only the 5 GHz band. In 2007, the FCC began requiring that devices operating on 5.250–5.350 GHz and 5.470–5.725 GHz must employ dynamic frequency selection (DFS) and transmit power control (TPC) capabilities. This is to avoid interference with weather-radar and military applications. On June 10, 2015, the FCC approved a new ruleset for 5 GHz device operation (called the "New Rules"), which adds 160 and 80 MHz channel identifiers, and re-enables previously prohibited DFS channels, in Publication Number 905462. In Europe or Japan the 2.4 GHz band is also free for use, but precise check has to be carried out for each channel used as there may be differences among individual countries, even in Europe. European standard EN 301 893 covers 5.15–5.725 GHz operation, and v1.8.1 is in force. Good starting point for the check is “List of WLAN channels” on Wikipedia.
GA 730640 Page 56 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Features Description
Points Static
Nodes Static
Type Master/Client – Point to multipoint
Data rate 11 – 1000 Mbit/s
Average throughput 5 – 600 Mbit/s
Range 10 m – 250 m (usually up to 50 m; upper part of the range only with adequate antenna and higher transmit power)
Frequency 2,4 / 3,7 / 5,0 GHz
Spectrum use public
MIMO In n, ac
Point to point In 5 GHZ band
Point to multipoint Usually 2,4 GHz
Latency 1-10 ms
Table 6.2 – 802.11a/b/g/n/ac characteristics
6.3.2.4.2. Standard 802.11ah (HayLow) This part has been taken and adapted from Wikipedia [3]. IEEE 802.11ah is a wireless networking protocol that is an amendment of the IEEE 802.11-2007 wireless networking standard. It uses sub- 1 GHz license-exempt bands to provide extended range Wi-Fi networks, compared to conventional Wi-Fi networks operating in the 2.4 GHz and 5 GHz bands. It also benefits from lower energy consumption, allowing the creation of large groups of stations or sensors that cooperate to share the signal, supporting the concept of the Internet of Things (IoT). It is a very new standard proposed by WiFi alliance in 2016. The special qualities – high range and low power are the reasons to investigate it separately from basic WiFi standards mentioned in the previous section.
GA 730640 Page 57 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
A benefit of 802.11ah is extended range, making it useful for rural communications. Compared to cell phone networks it is more suitable for relatively static networks without real-time switching the connections among end client devices. A prominent aspect of 802.11ah is the behaviour of stations that are grouped to minimize contention on the air media, use relay to extend their reach, use little power thanks to predefined wake/doze periods, are still able to send data at high speed under some negotiated conditions and use sectored antennas. It uses the 802.11a/g specification that is down sampled to provide 26 channels, each of them able to provide 100 kbit/s throughput. It can cover a one-kilometer radius. It aims at providing connectivity to thousands of devices under an access point. Data rates up to 234 Mbit/s are achieved only with the maximum of four spatial streams using one 16 MHz-wide channel. Various modulation schemes and coding rates are defined by the standard and are represented by a Modulation and Coding Scheme (MCS) index value. A Relay Access Point (AP) is an entity that logically consists of a Relay and a networking station (STA), or client. The relay function allows an AP and stations to exchange frames with one another by the way of a relay. The introduction of a relay allows stations to use higher MCSs (Modulation and Coding Schemes) and reduce the time stations will stay in Active mode. This improves battery life of stations. Relay stations may also provide connectivity for stations located outside the coverage of the AP. There is an overhead cost on overall network efficiency and increased complexity with the use of relay stations. To limit this overhead, the relaying function shall be bi- directional and limited to two hops only. The partition of the coverage area of a Basic Service Set (BSS) into sectors, each containing a subset of stations, is called sectorization. This partitioning is achieved through a set of antennas or a set of synthesized antenna beams to cover different sectors of the BSS. The goal of the sectorization is to reduce medium contention or interference by the reduced number of stations within a sector and/or to allow spatial sharing among overlapping BSS (OBSS) APs or stations. Security is comparable to 802.11a/b/g/n standards.
Features Description
Points Static or slow moving
Nodes Static
Type Master/Client – Point to multipoint
Data rate 0,65 – 234 Mbit/s
GA 730640 Page 58 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Features Description
Average throughput 0,1 – 100 Mbit/s
Range 100 m – 1000 m
Frequency ISM band (868 MHz Europe, 908/916 MHz USA)
Spectrum use public
MIMO n.a.
Point to point yes
Point to multipoint yes
Latency ? ms
Table 6.3 – 802.11ah characteristics
6.3.2.4.3. Standard 802.11p (ETSI ITS-G5) This part has originates mostly from the author’s previous knowledge of the technology and ETSI standards mentioned below. 802.11p was considered for dedicated short-range communications (DSRC), a U.S. Department of Transportation project based on the Communications access for land mobiles (CALM) architecture of the International Organization for Standardization for vehicle-based communication networks, particularly for applications such as toll collection, vehicle safety services, and commerce transactions via cars. In Europe, 802.11p was used as a basis for the ITS-G5 standard, supporting the GeoNetworking protocol for vehicle to vehicle (V2V) and vehicle to infrastructure (V2I) communication. ITS G5 and GeoNetworking is being standardised by the European Telecommunications Standards Institute group for Intelligent Transport Systems in a set of standards (ETSI ES 202 663, ETSI EN 302 571). It covers the frequency ranges:
· ITS-G5A: Operation of ITS-G5 in European ITS frequency bands dedicated to ITS for safety related applications in the frequency range 5,875 GHz to 5,905 GHz.
· ITS-G5B: Operation in European ITS frequency bands dedicated to ITS non-safety applications in the frequency range 5,855 GHz to 5,875 GHz.
GA 730640 Page 59 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· ITS-G5D: Operation of ITS applications for the future applications in the frequency range 5,905 GHz to 5,925 GHz.
Features Description
Points moving (150 km/h or more)
Nodes Static/moving
Type Master/Client – Point to multipoint
Data rate 6 – 108 Mbit/s
Average throughput >1 Mbit/s
Range 50 m – 300 m
Frequency 5,850 – 5,925 GHz
Spectrum use unlicensed
MIMO n.a.
Point to point In 5 GHZ band
Point to multipoint Usually 2,4 GHz
Latency 40 - 200 ms
Table 6.4 802.11p characteristics
6.3.2.4.4. IEEE 802.15.1 (Bluetooth) This part has been taken and adapted from Wikipedia [3] pages developed by Bluetooth Special Interest Group. The Bluetooth standard is defined for very short ranges up to 10 m for the most widespread revision 2.1. For the higher version up to 4.x higher transmit power is specified and higher range up to 100 m is possible. But the principle application is in the area of low-power communications over short distances, mainly in one room. The main application area is office devices networking and transmission of bigger blocks of data.
GA 730640 Page 60 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Typical data rate is 700 kbit/s. Works in the ISM band of 2.4 GHz. It is quite immune to interference due to the use of FHSS/GMSK modulation using frequency hops (1600 per second) for 79 frequencies. The transmission is secured with 128 bit AES cryptographic protocol which is fully sufficient for most types of time limited transmission sessions except full-time 24/7. Supports stars type of network: point-to-point, point-to-multipoint. Up to 7 devices can be connected to one master in a so called pico-network. More masters can be used to build a bigger network.
Features Description
Points Static or slow moving
Nodes Static
Type Master/Client – Point to multipoint
Data rate typ. 1 (up to 10) Mbit/s
Average throughput typ. 0,1 – 0,5 (up to 5) Mbit/s
Range 10 m – 100 m (usually up to 10 m; upper part of the range only with adequate antenna and higher transmit power)
Frequency 2,4 GHz ISM band
Spectrum use public
MIMO n.a.
Latency 10 ms
Table 6.5 802.15.1 Bluetooth characteristics
6.3.2.5. IEEE 802.15.4 The 802.15.4 standard defines
· physical layer
· media access control (MAC) layer
GA 730640 Page 61 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models for low-rate WPANs – wireless personal area networks. Several wireless technologies are built around this standard and add the necessary higher communication layers.
6.3.2.5.1. 802.15.4 ZigBee This part has been taken and compiled from Wikipedia [3], author’s knowledge and archives, ZigBee Alliance pages [27] and Radio-Electronics.com [28]. ZigBee industry standard has been defined and developed by a strong industry consortium, the ZigBee Alliance, which is based on IEEE 802.15.4. The ZigBee standard is defined for short ranges around 100 m and above, up to around 1 km, if higher transmit power is used. The main focus is on low data rate and low power. ZigBee Alliance developed specifications of network layer, application layer, ZigBee device objects and manufacturer/defined application objects. A big advantage of the specification is the fact that the software implementation is relatively simple and the foot-print is lower than 256 KB. The main application area is industrial wireless networking for monitoring and control: sensor to machine, machine to machine and machine to control centre data transmission of small blocks of data. Typical data rate is 20 – 250 kbit/s. But this is highly different from the useful data rate as it is expected that the nodes use the data transmission only at a fraction of the working time. ZigBee works in the ISM band of 868 MHz (Europe), 915 MHz (US), 784 MHz (China) and 2.4 GHz. It is quite immune to interference due to the use of O-QPSK/DSSS modulation. The transmission is secured with symmetrical 128 bit AES cryptographic protocol which is fully sufficient for most types of time limited transmission sessions except full-time 24/7. But thanks to the fact that the transmitted packets and transmission sessions are short it is secure enough for most industrial applications. Multi-hop transmission is available hence different types of networks can be set up: star, tree and mesh. Hundreds of devices can be connected to one master through the network. Coordinator device controls the network and routing device throughout the network care about the packet routing. If real-time response is required network devices may also use Guaranteed Time Slots (GTS), which by definition do not use CSMA. Nevertheless any additional hop in transmission increases latency proportionally. The ZigBee protocol is freely available only for non-commercial applications. For commercial purposes license is required.
GA 730640 Page 62 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Features Description
Points Static or slow moving
Nodes Static
Type Master/Client – Point to multipoint
Data rate 20/40 kbit/s for ISM band, 250 kbit/s for 2,4 GHz band
Average throughput 1 – 50 kbit/s
Range 100 m – 1000 m (usually up to 300 m; upper part of the range only with adequate antenna and higher transmit power)
Frequency 2,4 GHz band, ISM band (868 MHz Europe, 908/916 MHz USA)
Spectrum use public
MIMO n.a.
Latency 10 ms
Table 6.6 - 802.15.4 ZigBee characteristics
6.3.2.5.2. 6LoWPAN 6LoWPAN is an acronym of IPv6 over Low power Wireless Personal Area Networks. 6LoWPAN is the name of a concluded working group in the Internet area of the IETF. The 6LoWPAN group has defined encapsulation and header compression mechanisms that allow IPv6 packets to be sent and received over IEEE 802.15.4 based networks. IPv4 and IPv6 are the work horses for data delivery for local-area networks, metropolitan area networks, and wide-area networks such as the Internet. Likewise, IEEE 802.15.4 devices provide sensing communication- ability in the wireless domain. The inherent natures of the two networks though, are different.
GA 730640 Page 63 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
The base specification developed by the 6LoWPAN IETF group is RFC 4944 (updated by RFC 6282 with header compression and by RFC 6775 with neighbor discovery optimizations). The problem statement document is RFC 4919. IPv6 over Bluetooth Low Energy (BLE) is defined in RFC 7668.
6.3.2.5.3. Thread This part has been taken and adapted from Wikipedia [3] and Radio-Electronics.com [28]. Thread is an effort of over 50 companies to standardize on a closed-documentation, royalty-free protocol running over 6LoWPAN to enable home automation. It was launched in the second half of 2015. The protocol will most directly compete with Z-Wave and Zigbee IP. In July 2014, the "Thread Group" alliance was announced, which today is a working group with the companies Nest Labs (a subsidiary of Alphabet/Google), Samsung, ARM Holdings, Qualcomm, NXP Semiconductors/Freescale, Silicon Labs, Big Ass Solutions, Somfy, OSRAM, Tyco International, and the lock company Yale in an attempt to have Thread become the industry standard by providing Thread certification for products. Thread uses 6LoWPAN, which in turn uses the IEEE 802.15.4 wireless protocol with mesh communication, as does ZigBee and other systems. Thread however is IP-addressable, with cloud access and AES encryption. It currently supports up to 250 devices in one local network mesh. An "AS IS" BSD licensed free and open-source implementation of Thread (called "OpenThread") has also been released by Nest. As mentioned above, Thread uses 6LoWPAN, which is based on the use of a connecting router, called an edge router (Thread calls their edge routers Border Routers). Unlike other proprietary networks, 6LoWPAN, like any network with edge routers, does not maintain any application layer state because such networks forward datagrams at the network layer. This means that 6LoWPAN remains unaware of application protocols and changes. This lowers the processing power burden on edge routers. It also means that Thread does not need to maintain an application layer. Thread states that multiple application layers can be supported, as long as they are low-bandwidth and are able to operate over IPv6. Thread touts that there is no single point of failure in its system. However, if the network is only set up with one edge router, then this can serve as a single point of failure. The edge router or another router can assume the role of Leader for certain functions. If the Leader fails, another router or edge router will take its place. This is the main way that Thread guarantees no single point of failure. Thread promises a high level of security. Only devices that are specifically authenticated can join the network. All communications through the network are secured with a network key.
GA 730640 Page 64 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Features Description
Points Static or slow moving
Nodes Static
Type Master/Client – Point to multipoint
Data rate 250 kbit/s for 2,4 GHz band
Average throughput 1 – 50 kbit/s
Range 10 m – 100 m (usually up to 30 m)
Frequency 2,4 GHz band, ISM band (868 MHz Europe, 908/916 MHz USA)
Spectrum use public
MIMO n.a.
Latency 100 ms
Table 6.7 - 802.15.4 Thread characteristics
6.3.2.6. WiMAX (IEEE 802.16) This part has been taken and compiled from Wikipedia [3], author’s knowledge and archives and FreeWimaxInfo.com [29]. WiMAX standard has been defined and developed in 2003 as an IEEE 802.16a standard. WiMAX refers to interoperable implementations of the IEEE 802.16 family of wireless-networks standards ratified by the WiMAX Forum. It is defined for long ranges of 10 km and above, predominantly at LOS (Line-of-sight). The main focus is on high data rate and high ranges. The high transmission distance is the main characteristics which differentiates WiMAX from WiFi. The original version of the standard on which WiMAX is based (IEEE 802.16) specified a physical layer operating in the 10 to 66 GHz range. 802.16a, updated in 2004 to 802.16-2004, added specifications for the 2 to 11 GHz range. IEEE 802.16e-2005 improves upon IEEE 802.16-2004, mainly by:
GA 730640 Page 65 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· Adding support for mobility (soft and hard handover between base stations). This is seen as one of the most important aspects of 802.16e-2005, and is the very basis of Mobile WiMAX; WiMAX can handle speeds of 120 km/h
· Advanced antenna diversity schemes, and hybrid automatic repeat-request (HARQ)
· Adaptive antenna systems (AAS) and MIMO technology
· Introducing downlink sub-channelization, allowing administrators to trade coverage for capacity or vice versa
· Adding an extra quality of service (QoS) class for VoIP applications.
Modulation type SOFDMA (used in 802.16e-2005) and OFDM256 (802.16d) are not compatible thus equipment will have to be replaced if an operator is to move to the later standard (e.g., Fixed WiMAX to Mobile WiMAX). There is no uniform global licensed spectrum for WiMAX, however the WiMAX Forum published three licensed spectrum profiles: 2.3 GHz, 2.5 GHz and 3.5 GHz, in an effort to drive standardization and decrease cost. Another advantage of WiMAX is that enables communication over a maximum distance of 50 km – compared to 100 m for WiFi. Naturally, the longer the distance, the slower the data rate,. Ideally, speeds of around 10 Mbit/s could be achieved with a range of 1 – 6 miles (1.6 – 9.7 km). WiMAX uses a QoS mechanism based on connections between the base station and the user device. Each connection is based on specific scheduling algorithms. Newer standard versions are in development, adding multi-hop relay (IEEE 802.16j), up to 100 Mbit/ rate for mobile and 1 Gbit/s for fixed stations, etc. (IEEE 802.16m/n/p). Security of the transmission is provided by AES 128/256 bit symmetrical keys. Additionally, it is recreated at intervals for optimal security. The 802.16e-2005 amendment specifies Privacy and Key Management Protocol Version 2 as the key management implementation. This system handles the transfer of keys between the base station and the subscriber station by using X.509 digital certificates and RSA public-key algorithm. Additional security is provided by refreshing the keys and connections at frequent intervals. Standard authentication protocol is employed - user and device authentication for WiMAX consists of certificate support using Internet Engineering Task Force (IETF) Extensible Authentication Protocol (EAP). The WiMAX technology is more complex and less commercialized as is WiFi hence it is considerably more costly than WiFi. GA 730640 Page 66 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Features Description
Points Static or moving
Nodes Static or moving (up to 120 km/h)
Type Master/Client – Point to multipoint
Data rate 6 – 376 Mbit/s
Average throughput 1 – 50 kbit/s
Range 1000 m – 50 km (with decreasing available data rate; high rates only with MIMO)
Frequency 2,4 GHz ISM, 2,5-2,7 GHz licensed, 3,5 GHz lic., 5,8 GHz unlic., 10,5 GHz lic.
Spectrum use public/licensed
MIMO up to 4x4
Latency 50 ms
Table 6.8 - 802.16 WiMAX characteristics
6.3.2.7. Z-Wave This part has been taken and compiled from Sigma Design company web pages [30], the ITU standard and Radio-Electronics.com [28]. Z-Wave industry standard is based upon the ITU 9959 standard and has been defined and developed by a Danish start-up Zen-Sys then acquired by the Sigma Design company. It is currently supported by a strong industry consortium, the Z-Wave Alliance. The Alliance concentrates mainly on public promotion and certification of the devices as the specifications are public and free to use. The principle goal is to achieve 100 % interoperability, even ensuring backwards compatibility. The Z-Wave standard is defined for short ranges around 100 m. The main focus is on low data rate and low power, especially for home networking among sensors, actuators, detectors, controllers – generally for IoT. – data transmission of small blocks of data. Accented is the very low power consumption to enable multi-year operation of miniature battery-powered devices.,
GA 730640 Page 67 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Typical data rate is 9,6, 40 and 100 kbit/s. But this is highly different from the useful data rate (throughput) as it is expected that the nodes use the data transmission only at a fraction of the working time. Z-Wave works in the ISM band of 868 MHz (Europe), 915 MHz (US). It is moderately immune to interference due to the use of FSK/GFSK modulation. The transmission is secured with symmetrical 128 bit AES cryptographic protocol which is fully sufficient for most types of time limited transmission sessions except full-time 24/7. But thanks to the fact that the transmitted packets and transmission sessions are short it is secure enough for most industrial applications. One primary controller manages the whole network. Up to 232 devices can be connected to this master through the network. Each node may act as a repeater in the mesh network. A secondary controller can be configured for back-up but may not change the network. Multi-hop transmission (up to 4 x) is available hence different types of networks can be set up: star, tree and mesh. On hop can range up to 40 m, 4 hops then lead to range of about 150 m. Mesh type is preferred topology of operation. The Z-Wave protocol is freely available. Even open-source software implementations are publicly available.
Features Description
Points Static or slow moving
Nodes Static
Type Master/Client – Point to multipoint
Data rate 9,6/40/100 kbit/s
Average throughput 0,1 – 1 kbit/s
Range 20 m – 150 m (typically up to 100 m;)
Frequency ISM band (868 MHz Europe, 908/916 MHz USA)
Spectrum use public
MIMO n.a.
Latency typ. 200 ms (increases with nr. of hops/retransmissions)
GA 730640 Page 68 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Table 6.9 - Z-Wave characteristics
6.3.2.8. EnOcean This part has been taken and compiled from Wikipedia [3], EnOcean company web pages [31], the ITU standard and Radio-Electronics.com [28]. EnOcean technology combines energetically efficient exploitation of slight mechanical motion and other potentials from the environment, such as indoor light and temperature differences, using the principles of energy harvesting in order to transform such energy fluctuations or differences into usable electrical energy. Electromagnetic, solar, and thermoelectric energy converters are used. The harvested energy is then used to supply power to the respective sensor or actuator and, simultaneously, send data over the wireless link. EnOcean-based products (such as sensors and light switches) perform without batteries and are engineered to operate maintenance-free. The radio signals from these sensors and switches can be transmitted wirelessly over a distance of up to 300 meters in the open and up to 30 meters inside buildings. Early designs from the founding company (EnOcean GmbH) used piezo generators, but were later replaced with electromagnetic energy sources to increase the service life to 100 operations a day for more than 25 years. EnOcean wireless data packets are relatively small, with the packet being only 14 bytes long and are transmitted at 125 kbit/s. RF energy is only transmitted for the 1's of the binary data, reducing the amount of power required. Three packets are sent at pseudo-random intervals reducing the possibility of RF packet collisions. Modules optimized for switching applications transmit additional data packets on release of push-button switches, enabling other features such as light dimming to be implemented. The transmission frequencies used for the devices are 902 MHz, 928.35 MHz, 868.3 MHz and 315 MHz. A group of companies including EnOcean, Texas Instruments, Omnio, Sylvania, Masco, and MK Electric formed the EnOcean Alliance in April 2008 as a non-profit, mutual benefit corporation. The EnOcean Alliance has drawn up the application level protocols are referred to as EEPs (EnOcean Equipment Profiles). The international wireless standard ISO/IEC 14543-3-10 and the Alliance’s EEP lay the foundation for a fully interoperable, open wireless technology. More than 250 companies currently belong to the EnOcean Alliance. For applying the complete specification license fees have to be paid to the Alliance, unless the supplier develops a solution from scratch based on the public standard. But interoperability with COTS products cannot be achieved this way. First 3 layers of the ISO/OSI model are defined in the standard. There are several key aspects for the physical layer: GA 730640 Page 69 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· GFSK modulation: The EnOcean radio interface uses a form of modulation known as GFSK: Gaussian Frequency Shift Keying. Frequency Shift Keying is a form of frequency modulation where the signal frequency is changed between two frequencies dependent upon the modulation. In the case of the EnOcean radio signal the shift is ±62.5kHz of the central carrier position. The +62.5 kHz position is for the code used to indicate logical "1" and the -62.5 kHz position is the code used to indicate a logical "0".
· The EnOcean standard allows for the use of different GFSK filter parameters dependent upon the required national regulation requirements.
· EnOcean Frequencies: The EnOcean radio interface specification states that the system can operate within a variety of ISM bands. However the individual frequencies are specified for which the system is to be used are specified within the standard. Currently two frequencies are specified: 902.875MHz which is aimed at the North American market and 928.35MHz which is aimed at the Japanese market. The standard states that the aim of the specification is to be frequency independent and therefore additional frequencies may be introduced as new markets or requirements arise.
EnOcean Frame: Data to be transmitted is assembled into frames. This enables synchronisation, and the correct reception of the data, etc. Payload can range from 1 byte to 255 bytes.
Features Description
Points Static
Nodes Static
Type Master/Client – Point to multipoint
Data rate 125 kbit/s in the ISM band,
Average throughput 0.5 – 1.5 kbit/s
Range 30 m – 100 m indoor (up to 300 m outdoor)
Frequency ISM band (868 MHz Europe, 908/916 MHz USA)
Spectrum use public
GA 730640 Page 70 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Features Description
MIMO n.a.
Latency typ. 30 ms
Table 6.10 – EnOcean characteristics
6.3.3. Mobile Cellular Networks
This part has been taken and adapted from Wikipedia [3] and the NGTC project [4]. In the following paragraphs the Mobile Cellular Networks are characterized with emphasis on data transmission over voice transmission.
6.3.3.1. Basics A cellular network or mobile network is a communication network where the last link is wireless. The network is distributed over land areas called cells, each served by at least one fixed-location transceiver, known as a cell site or base station. This base station provides the cell with the network coverage which can be used for transmission of voice, data and others. A cell might use a different set of frequencies from neighbouring cells, to avoid interference and provide guaranteed service quality within each cell. Cellular networks offer a number of desirable features:
· More capacity than a single large transmitter, since the same frequency can be used for multiple links as long as they are in different cells
· Mobile devices use less power than with a single transmitter or satellite since the cell towers are closer
· Larger coverage area than a single terrestrial transmitter, since additional cell towers can be added indefinitely and are not limited by the horizon
In a cellular radio system, a land area to be supplied with radio service is divided into cells, in a pattern which depends on terrain and reception characteristics but which can consist of roughly hexagonal, square, circular or some other regular shapes, although hexagonal cells are conventional. Each of these cells is assigned with multiple frequencies (f1 – f6) which have corresponding radio base stations. The group of frequencies can be reused in other cells, provided that the same frequencies are not reused in adjacent neighboring cells as that would cause co- channel interference.
GA 730640 Page 71 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Major telecommunications providers have deployed voice and data cellular networks over most of the inhabited land area of the Earth. This allows mobile phones and mobile computing devices to be connected to the public switched telephone network and public Internet.
6.3.3.1.1. Spectrum Usage Radio frequencies used for cellular networks differ in ITU Regions (Americas, Europe, Africa and Asia). The first commercial standard for mobile connection in the United States was AMPS, which was in the 800 MHz frequency band. In Nordic countries of Europe, the first widespread automatic mobile network was based on the NMT-450 standard, which was in the 450 MHz band. As mobile phones became more popular and affordable, mobile providers encountered a problem because they couldn't provide service to the increasing number of customers. They had to develop their existing networks and eventually introduce new standards, often based on other frequencies. Some European countries (and Japan) adopted TACS operating in 900 MHz. The GSM standard, which appeared in Europe to replace NMT-450 and other standards, initially used the 900 MHz band too. As demand grew, carriers acquired licenses in the 1,800 MHz band. (Generally speaking, lower frequencies allow carriers to provide coverage over a larger area, while higher frequencies allow carriers to provide service to more customers in a smaller area.) In the U.S., the analog AMPS standard that used the cellular band (800 MHz) was replaced by a number of digital systems. Eventually, IS-136 on these frequencies was replaced by most operators with GSM. GSM had already been running for some time on US PCS (1,900 MHz) frequencies. And, some NMT-450 analog networks have been replaced with digital networks using the same frequency. In Russia and some other countries, local carriers received licenses for 450 MHz frequency to provide CDMA mobile coverage area.Many GSM phones support three bands (900/1,800/1,900 MHz or 850/1,800/1,900 MHz) or four bands (850/900/1,800/1,900 MHz), and are usually referred to as tri-band and quad-band phones, or world phones; with such a phone one can travel internationally and use the same handset. This portability is not as extensive with IS-95 phones; however, as IS-95 networks do not exist in most of Europe.
6.3.3.1.2. Cell signal encoding To distinguish signals from several different transmitters, time division multiple access (TDMA), frequency division multiple access (FDMA), code division multiple access (CDMA), and orthogonal frequency division multiple access (OFDMA) were developed. With TDMA, the transmitting and receiving time slots used by different users in each cell are different from each other.
GA 730640 Page 72 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
With FDMA, the transmitting and receiving frequencies used by different users in each cell are different from each other. In a simple taxi system, the taxi driver manually tuned to a frequency of a chosen cell to obtain a strong signal and to avoid interference from signals from other cells. The principle of CDMA is more complex, but achieves the same result; the distributed transceivers can select one cell and listen to it. Other available methods of multiplexing such as polarization division multiple access (PDMA) cannot be used to separate signals from one cell to the next since the effects of both vary with position and this would make signal separation practically impossible. Time division multiple access is used in combination with either FDMA or CDMA in a number of systems to give multiple channels within the coverage area of a single cell.
6.3.3.1.3. Structure of the cellular network A simple view of the cellular mobile-radio network consists of the following: · A network of radio base stations forming the base station subsystem.
· The core circuit switched network for handling voice calls and text
· A packet switched network for handling mobile data
· The public switched telephone network to connect subscribers to the wider telephony network
This network is the foundation of the GSM system network. There are many functions that are performed by this network in order to make sure customers get the desired service including mobility management, registration, call set-up, and handover.
6.3.3.1.4. Cellular handover As the phone user moves from one cell area to another cell while a call is in progress, the mobile station will search for a new channel to attach to in order not to drop the call. Once a new channel is found, the network will command the mobile unit to switch to the new channel and at the same time switch the call onto the new channel. With CDMA, multiple CDMA handsets share a specific radio channel. The signals are separated by using a pseudonoise code (PN code) specific to each phone. As the user moves from one cell to another, the handset sets up radio links with multiple cell sites (or sectors of the same site) simultaneously. This is known as "soft handoff" because, unlike with traditional cellular technology, there is no one defined point where the phone switches to the new cell.
GA 730640 Page 73 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
6.3.3.1.5. Coverage comparison
Frequency (MHz) Cell radius (km) Cell area (km2) Relative Cell Count
450 50 7500 1
950 27 2200 3.3
1800 14.0 600 12.2
2100 12.0 450 16.2
Table 6.11 – Coverage comparison – approximate values for free surface
6.3.3.2. Circuit Switched Data Services in GSM It has to be noted that GSM 1st generation, including GSM-R (GSM for Railway), and especially CSD (Circuit-Switched Data) services are considered as obsolete for new applications. GSM solutions suppliers will gradually stop supplying systems to the market. Only for GSM-R, there is a guarantee that suppliers will continue to support their products until 2030. Data services in GSM, a s well as GSM-R, are described below.
6.3.3.2.1. Basic and High-speed CS data transmission · Basic data transmission standardized with only 9.6 kbit/s
§ advanced coding allows 14,4 kbit/s § too low data rate for Internet and multimedia applications § acceptable for low demand data transmission applications · HSCSD (High-Speed Circuit Switched Data)
§ bundling of several time-slots to get higher data rate § AIUR (Air Interface User Rate) § (e.g., 57.6 kbit/s using 4 slots, 14.4 each) § advantage: ready to use, constant quality, simple · disadvantage: channels blocked for other users
6.3.3.2.2. GPRS (General Packet Radio Service) · Packet switching
§ using free slots only if data packets ready to send § (e.g., 115 kbit/s using 8 slots temporarily) GA 730640 Page 74 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
§ standardization 1998, introduced 2000 · GPRS performance figures:
§ 3 different reliability classes: o between 10-2 to 10-9 probability of lost SDU (Service Data Unit), duplicate SDU, out of sequence SDU or corrupt SDU § 4 different delay classes: o between 0,5 s to 75 s of mean value · between 1,5 s to 375 s of 95 % percentile value
6.3.3.2.3. UMTS and IMT-2000 Proposals for IMT-2000 (International Mobile Telecommunications)
· UWC-136, cdma2000, WP-CDMA
· UMTS (Universal Mobile Telecommunications System) from ETSI
UMTS Characteristics:
· UTRA (was: UMTS, now: Universal Terrestrial Radio Access)
§ enhancements of GSM o EDGE (Enhanced Data rates for GSM Evolution): § EDGE is a digital mobile phone technology that allows improved data transmission rates as a backward-compatible extension of GSM. EDGE is considered a pre-3G radio technology and is part of ITU's 3G definition § EDGE is standardized also by 3GPP as part of the GSM family § EDGE can carry a bandwidth up to 236 kbit/s (with end-to-end latency of less than 150 ms) for 4 timeslots (theoretical maximum is 473.6 kbit/s for 8 timeslots) in packet mode. This means it can handle four times as much traffic as standard GPRS o CAMEL (Customized Application for Mobile Enhanced Logic) o VHE (virtual Home Environment) § fits into GMM (Global Multimedia Mobility) initiative from ETSI o requirements - min. 144 kbit/s rural (goal: 384 kbit/s) - min. 384 kbit/s suburban (goal: 512 kbit/s) - up to 2 Mbit/s urban § The Core Network (CN) and thus the Interface Iu, too, are separatedinto two logical domains: o Circuit Switched Domain (CSD) GA 730640 Page 75 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
- Circuit switched service incl. signaling - Resource reservation at connection setup - GSM components (MSC, GMSC, VLR) - IuCS o Packet Switched Domain (PSD) - GPRS components (SGSN, GGSN) - IuPS § Release 99 uses the GSM/GPRS network and adds a new radio access § Support of mobility: o Multicasting of data via several physical channels - Enables soft handover - FDD mode only o Uplink - simultaneous reception of UE data at several Node Bs - Reconstruction of data at Node B, SRNC or DRNC o Downlink - Simultaneous transmission of data via different cells - Different spreading codes in different cells § Handover: o From and to other systems (e.g., UMTS to GSM)
Service Profile Bandwidth Transport mode
High Interactive MM 128 kbit/s Circuit switched Bidirectional, video telephone
High MM 2 Mbit/s Packet switched Low coverage, max. 6 km/h
Medium MM 384 kbit/s Circuit switched asymmetrical, MM, downloads
Switched Data 14.4 kbit/s Circuit switched
Simple Messaging 14.4 kbit/s Packet switched SMS successor, E-Mail
Voice 16 kbit/s Circuit switched
Table 6.12 – UMTS profiles GA 730640 Page 76 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
6.3.3.3. Evolved High Speed Packet Access (HSPA, HSPA+) Evolved High Speed Packet Access, or HSPA+, or HSPA(Plus), or HSPAP is a technical standard for wireless, broadband telecommunication. It is the second phase of HSPA which has been introduced in 3GPP release 7 and being further improved in later 3GPP releases. HSPA+ can achieve data rates of up to 42.2 Mbit/s. It introduces antenna array technologies such as beamforming and Multiple-input multiple- output communications (MIMO). Beam forming focuses the transmitted power of an antenna in a beam towards the user’s direction. MIMO uses multiple antennas at the sending and receiving side. Further releases of the standard have introduced dual carrier operation, i.e. the simultaneous use of two 5 MHz carriers. The technology also delivers significant battery life improvements and dramatically quicker wake-from-idle time, delivering a true always-on connection. HSPA+ is an evolution of HSPA that upgrades the existing 3G network and provides a method for telecom operators to migrate towards 4G speeds that are more comparable to the initially available speeds of newer LTE networks without deploying a new radio interface. HSPA+ should not be confused with LTE though, which uses an air interface based on Orthogonal frequency- division multiple access modulation and multiple access. Advanced HSPA+ is a further evolution of HSPA+ and provides data rates up to 84.4 and 168 Megabits per second (Mbit/s) to the mobile device (downlink) and 22 Mbit/s from the mobile device (uplink) under ideal signal conditions. Technically these are achieved through the use of a multiple-antenna technique known as MIMO (for "multiple-input and multiple-output") and higher order modulation (64QAM) or combining multiple cells into one with a technique known as Dual-Cell HSDPA.
6.3.3.4. High Speed Downlink Packet Access (HSDPA) High Speed Downlink Packet Access (HSDPA) is an enhanced 3G (third-generation) mobile communications protocol in the High-Speed Packet Access (HSPA) family, also dubbed 3.5G, 3G+, or Turbo 3G, which allows networks based on Universal Mobile Telecommunications System (UMTS) to have higher data speeds and capacity. HSDPA has been introduced with 3GPP Release 5, which also accompanies an improvement on the uplink providing a new bearer of 384 kbit/s. The previous maximum bearer was 128 kbit/s. As well as improving data rates, HSDPA also decreases latency and so the round trip time for applications. HSPA+ introduced in 3GPP Release 7 further increases data rates by adding 64QAM modulation, MIMO and Dual-Cell HSDPA operation, i.e. two 5 MHz carriers are used
GA 730640 Page 77 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models simultaneously. Even higher speeds of up to 337.5 Mbit/s are possible with Release 11 of the 3GPP standards. The first phase of HSDPA has been specified in the 3GPP release 5. Phase one introduces new basic functions and is aimed to achieve peak data rates of 14.0 Mbit/s with significantly reduced latency. The improvement in speed and latency reduces the cost per bit and enhances support for high-performance packet data applications. HSDPA is based on shared channel transmission and its key features are shared channel and multi- code transmission, higher-order modulation, short transmission time interval (TTI), fast link adaptation and scheduling along with fast hybrid automatic repeat request (HARQ). Further new features are the High Speed Downlink Shared Channels (HS-DSCH), the adaptive modulation QPSK and 16QAM and the High Speed Medium Access protocol (MAC-hs) in base station. The upgrade to HSDPA is often just a software update for WCDMA networks. In general voice calls are usually prioritized over data transfer.
6.3.3.5. Long-Term Evolution (LTE)
Long-Term Evolution (LTE) is a standard for high-speed wireless communication for mobile phones and data terminals, based on the GSM/EDGE and UMTS/HSPA technologies. It increases the capacity and speed using a different radio interface together with core network improvements. The standard is developed by the 3GPP (3rd Generation Partnership Project) and is specified in its Release 8 document series, with minor enhancements described in Release 9. LTE is the upgrade path for carriers with both GSM/UMTS networks and CDMA2000 networks. The different LTE frequencies and bands used in different countries mean that only multi-band phones are able to use LTE in all countries where it is supported.
LTE is commonly marketed as 4G LTE, but it does not meet the technical criteria of a 4G wireless service, as specified in the 3GPP Release 8 and 9 document series, for LTE Advanced. The requirements were originally set forth by the ITU-R organization in the IMT Advanced specification. However, due to marketing pressures and the significant advancements that WiMAX, Evolved High Speed Packet Access and LTE bring to the original 3G technologies, ITU later decided that LTE together with the aforementioned technologies can be called 4G technologies. The LTE Advanced standard formally satisfies the ITU-R requirements to be considered IMT- Advanced. To differentiate LTE Advanced and WiMAX-Advanced from current 4G technologies, ITU has defined them as "True 4G".
GA 730640 Page 78 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
LTE offers throughput rates beyond 100 Mb/s and short latency of around 20 ms. To support this complex functionality, more intelligence must be built into the eNodeB than in its predecessor (3G NodeB). LTE applies the double concept of user-plane (user applications) and control-plane (network control traffic).
Following ITU, the peak data target of LTE is 15 b/s per Hz for downlink and 6,75 b/s per Hz for uplink. This can be realized with a deployment in 20 MHz bandwidth, and MIMO (8 x 8 in downlink, 4 x 4 in uplink). Under simulation, an average cell throughput of roughly 3 b/s per Hz for downlink (4 x 2) and 2 b/s per Hz for uplink (1 x 4) has been obtained. These figures are almost the same with FDD and TDD modes, in a Rural Macro-cellular deployment supporting high speed.
6.3.3.5.1. Frequency bands The LTE standard covers a range of many different bands, each of which is designated by both a frequency and a band number.
· in Europe 700, 800, 900, 1800, 2600 MHz (bands 3, 7, 20) are used;
· In North America, 700, 750, 800, 850, 1900, 1700/2100 (AWS), 2300 (WCS) 2500 and 2600 MHz (Rogers Communications, Bell Canada) are used (bands 2, 4, 5, 7, 12, 13, 17, 25, 26, 30, 41);
· 2500 MHz in South America;
· 800, 1800 and 2600 MHz in Asia (bands 1, 3, 5, 7, 8, 11, 13, 40)
· 1800 MHz and 2300 MHz in Australia and New Zealand (bands 3, 40).
As a result, phones and computerized devices from one country may not work in other countries. Users will need a multi-band capable device for roaming internationally or a specific band clone of the device for a specific country or region.
6.3.4. IoT Wide-Area Networks
Internet-of-Things (IoT) WANs are a specific branch of WANs, usually called LPWANs – Low-Power WANs, which are focused on providing services to thousands up to millions of low-power devices in order to ensure their data connection to monitoring and control centres. The specificity of those networks lie in the characteristics that the data primarily travel wirelessly from the “Thing” over the internet via IP protocol to a centrally located devices (monitoring servers or controllers).
GA 730640 Page 79 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Therefore, typically the uplink transfer is the major direction of data transport and downlink bandwidth is either limited or even impossible. This is in high contrast to other internet and data/voice transmission technologies which provide either balanced/symmetrical bandwidth or higher bandwidth in the downlink direction.
6.3.4.1. LoRaWAN This part has been taken and compiled from Wikipedia [3], Radio-Electronics.com [28], LoRa Alliance web pages [32] and Link Labs white papers [33]. LoRaWAN is a Low Power Wide Area Network with features that support low-cost, mobile, and secure bi-directional communication for Internet of Things (IoT), machine-to-machine (M2M), and smart city, and industrial applications. LoRaWAN is optimized for low power consumption and is designed to support large networks with millions and millions of devices. Innovative features of LoRaWAN include support for redundant operation, geolocation, low-cost, and low-power - devices can even run on energy harvesting technologies enabling the mobility and ease of use of Internet of Things. The frequency band used is ISM which is 868 MHz for Europe and 900-916 MHz for USA. It is the low power, wide-area network (LPWAN) global standard for carrier-operated networks, adopted by the LoRa Alliance. LoRaWAN network architecture is typically laid out in a star-of-stars topology in which gateways is a transparent bridge relaying messages between end-devices and a central network server in the backend. Gateways are connected to the network server via standard IP connections while end-devices use single-hop wireless communication to one or many gateways. All end-point communication is generally bi-directional, but also supports operation such as multicast enabling software upgrade over the air or other mass distribution messages to reduce the on air communication time. Communication between end-devices and gateways is spread out on different frequency channels and data rates. The selection of the data rate is a trade-off between communication range and message duration. Due to the spread spectrum technology, communications with different data rates do not interfere with each other and create a set of "virtual" channels increasing the capacity of the gateway. LoRaWAN data rates range from 0.3 kbps to 50 kbps. To maximize both battery life of the end-devices and overall network capacity, the LoRaWAN network server is managing the data rate and RF output for each end-device individually by means of an adaptive data rate (ADR) scheme. National wide networks targeting internet of things such as critical infrastructure, confidential personal data or critical functions for the society has a special need for secure communication. This has been solved by several layer of encryption: GA 730640 Page 80 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· Unique Network key (EUI64) ensure security on network level
· Unique Application key (EUI64) ensure end to end security on application level
· Device specific key (EUI128)
One of the big headache of LoRaWAN is complicated management of multiple per-device encryption keys both at the time of device production and on the server side. ETSI specification imposes a 1 % duty cycle limit on the communication between end-devices and the gateway which limits the possibility to transfer larger data volumes. The protocol is asynchronous hence it doesn’t support full acknowledgement of packet delivery so the packet losses may be significant. The LoRaWAN Specification document describes the LoRaWAN™ network protocol including MAC layer commands, frame content, security, flexible network frequency management, device EIRP and TX dwell time, power control, relay protection and more. Because LoRaWAN encrypts all traffic up and down on a one-to-one basis, implementing multicast transmissions is quite difficult. Operating a LoRaWAN network requires a paid license at the level of tens of KEUR annually. Hence operating it either autonomously or using some other’s network considerably increases OPEX.
Features Description
Points Static
Nodes Static
Type Master/Client – Point to multipoint
Data rate 0.3 – 50 kbit/s uplink
Average throughput 3 – 500 bit/s
Range up to 20 km
Frequency ISM band (868 MHz Europe, 908/916 MHz USA)
Spectrum use unlicensed
MIMO n.a.
GA 730640 Page 81 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Features Description
Latency typ. 4 – 120 s
Table 6.13 – LoRaWAN
6.3.4.2. Symphony Link This part has been taken and compiled from Wikipedia [3] and Link Labs white papers [33]. Symphony Link is a communication technology based on LoRa specifications but removes many various limitations. It is a synchronous protocol allowing full acknowledgment of packet delivery which enables very low packet loss and, in addition, deploying repeaters which highly expand the range without increasing latency. Repeaters are low-cost, low-power devices which brings higher range to users without adding major cost. It also adds Frequency Hopping Listen Before Talk which removes the duty cycle limit as for the LoRaWAN network. This results in the ability to multicast large files, e.g. firmware updates, which ensures easy, service-free upgrading of the end-devices. Symphony Link adds a QoS tiering system which enables to prioritize traffic for important devices. In fact Symphony Link yields 4x higher bandwidth than LoRaWAN. Also bigger payloads are allowed with Symphony Link than with LoRaWAN. While LoRaWAN security flaws pose a small risk for most users, the use of pre-shaped keys and identities create vulnerabilities. Symphony Link uses PKI which is considered unbreakable by NSA. With Symphony Link the host device configuration is always the same for all devices of the same type and the key exchange is handled via a PKI-based AES architecture. Symphony Link implements multicast session keys which allow for groups of devices to be addressed which also enables firmware OTA update.
Features Description
Points Static
Nodes Static
Type Master/Client – Point to multipoint
Data rate 10 – 250 kbit/s uplink
GA 730640 Page 82 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Features Description
Average throughput 0.1 – 50 kbit/s
Range up to 50 km
Frequency ISM band (868 MHz Europe, 908/916 MHz USA)
Spectrum use unlicensed
MIMO n.a.
Latency typ. 100 ms – 120 s
Table 6.14 – Symphony Link
LoRaWAN Symphony Link
Creator Semtech / LoRa Alliance Link Labs / IEEE 802.15.4
Coverage Carrier Operated Networks Customer-Deployed
MAC Focus Uplink Data Traffic Fully Bidirectional
MAC Controller Server Driven Gateway Driven
Downlink Latency 4s-120s 100ms-120s
Adaptive Data Rate Yes (Static) Yes (Dynamic)
Frequency Band Focus ITU Region 2 (Europe) ITU Region 1 (Americas, Etc.)
Table 6.15 – Comparison of LoRaWAN and Symphony Link
6.3.4.3. NarrowBand IoT (NB-IoT) This part has been taken and compiled from Wikipedia [3] and Radio-Electronics.com [28.] NB- IoT is a narrowband radio technology designed for the Internet of Things (IoT), and is one of a range of Mobile IoT (MIoT) technologies standardized by the 3rd Generation Partnership Project (3GPP). Other 3GPP IoT technologies include eMTC (enhanced Machine-Type Communication)
GA 730640 Page 83 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models and EC-GSM-IoT. The NB-IoT specification was frozen at Release 13 of the 3GPP specification (LTE- Advanced Pro), in June 2016. NB-IoT is a new 3GPP radio-access technology in the sense that it is not fully backward compatible with existing 3GPP devices. It is however designed to achieve excellent co-existence performance with legacy GSM, General Packet Radio Service (GPRS) and LTE technologies. NB-IoT requires 180 kHz minimum system bandwidth for both downlink and uplink, respectively. The choice of minimum system bandwidth enables a number of deployment options. A GSM operator can replace one GSM carrier (200 kHz) with NB-IoT. An LTE operator can deploy NB-IoT inside an LTE carrier by allocating one of the Physical Resource Blocks (PRB) of 180 kHz to NB-IoT. The air interface of NB-IoT is optimized to ensure harmonious coexistence with LTE, and thus such an “in- band” deployment of NB-IoT inside an LTE carrier will not compromise the performance of LTE or NB-IoT. An LTE operator also has the option of deploying NB-IoT in the guard-band of the LTE carrier. NB-IoT reuses the LTE design extensively, including the numerologies, downlink orthogonal frequency-division multiple-access (OFDMA), uplink single-carrier frequency-division multiple- access (SC-FDMA), channel coding, rate matching, interleaving, etc. This significantly reduces the time required to develop full specifications. Also, it is expected that the time required for developing NB-IoT products will be significantly reduced for existing LTE equipment and software vendors. The normative phase of NB-IoT work item in 3GPP started in September 2015 and the core specifications complete in June 2016. Commercial launch of NB-IoT products and services were expected to be around the end of 2016 and the beginning of 2017 wile chipsets have already entered production phase. NB-IoT focuses specifically on indoor coverage, low cost, long battery life, and enabling a large number of connected devices. NB-IoT targets latency insensitive applications. However, for applications like sending alarm signals, NB-IoT is designed to allow less than 10 s latency. The NB- IoT technology can either be deployed “in-band” in spectrum allocated to Long Term Evolution (LTE) - utilizing resource blocks within a normal LTE carrier, or in the unused resource blocks within a LTE carrier’s guard-band - or “standalone” for deployments in dedicated spectrum. It is also suitable for the re-farming of GSM spectrum.
Features Description
Points Static
Nodes Static
GA 730640 Page 84 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Features Description
Type Master/Client – Point to multipoint
Data rate 250 kbit/s downlink, 20 – 250 kbit/s uplink
Average throughput 1 – 50 kbit/s
Range above 10 km
Frequency GSM/LTE bands
Spectrum use licensed
MIMO n.a.
Latency typ. 1,6 – 10 s
Table 6.16 – NB-IoT
6.3.4.4. UNB/Sigfox This part has been taken and compiled from Wikipedia [3], Radio-Electronics.com [28] and SigFox company web pages [34]. SigFox is a narrowband (or ultra-narrowband – UNB) technology. It uses a standard radio transmission method called binary phase-shift keying (BPSK), and it takes very narrow chunks of spectrum and changes the phase of the carrier radio wave to encode the data. This allows the receiver to only listen in a tiny slice of spectrum which mitigates the effect of noise. It requires an inexpensive endpoint radio and a more sophisticated basestation to manage the network. Available data throughput is:
· Up to 140 messages per object per day
· Payload size for each message is 12 bytes
· Wireless throughput up to 100 bits per second
The ultra-narrow band technology means that the data transmission is slow and the payloads in frames are small. The BPSK modulation allows for very narrow band usage but it also limits the percentage of time the end-point is transmitting. Even the transmission in the downlink direction GA 730640 Page 85 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models is very limited as the technology is optimized for transfer of data from millions of sensors to the monitoring center. SigFox uses the same ISM band as LoRa or Symphony Link. The SigFox business model takes a top-down approach. The company owns all of its technology— from the backend data and cloud server to the endpoints software. But the differentiator is that SigFox is essentially an open market for the endpoints. SigFox gives away its endpoint technology to whatever silicon manufacturer or vendor wants it so long as certain business terms are agreed upon. Large manufacturers like STMicroelectronics, Atmel, and Texas Instruments make SigFox radios. SigFox thinks that allowing the application to be really inexpensive is the way to drive people to its market. SigFox endpoints use commodity MSK radios, and they are relatively inexpensive. A SigFox module can cost less than $10 in high volumes, so SigFox partners aren't bringing in much money from the hardware itself. SigFox makes its money by getting network operators to pay royalties on reselling its technology stack to customers. In other words, SigFox gives away the hardware enablers but sells the software/network as a service. In some cases, the company actually deploys the network and acts as the network operator. This is the case in France and in the US; when you buy LPWAN service there, you’re operating on a SigFox network. SigFox’s ultimate goal is to get large network operators from all over to world to deploy its networks. It has raised more than €100 million to do this and has great global reach. SigFox has been around since 2009 (longer than almost everyone else in the space), and It is likely the most aggressive marketer in IoT. SigFox is of the opinion that It is easier to work with mobile network operators or deploy networks itself and charge a small recurring fee than to sell expensive hardware at the endpoint.If you want to deploy a SigFox network, you have to work directly with SigFox—there isn't another option. Additionally, only one SigFox network can be deployed in an area, because the company has exclusive arrangements with network operators when they work together.
Features Description
Points Static
Nodes Static
Type Master/Client – Point to multipoint
Data rate 0,1 – 1 kbit/s uplink
GA 730640 Page 86 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Features Description
Average throughput 10 – 100 bit/s (with additional limit on the number of transactions per day)
Range 50 km
Frequency ISM band (868 MHz Europe, 908/916 MHz USA)
Spectrum use licensed
MIMO n.a.
Latency typ. 1,6 – 10 s
Table 6.17 – SigFox
6.3.5. Satellite technologies and services
This chapter has been taken over and adapted from the NGTC project [4]. Communication satellite service can be categorized by the following qualities:
· Coverage area o Regional o National o Global · Service type o Fixed service satellite (FSS) o Broadcast service satellite (BSS) o Mobile service satellite (MSS) · Use case o Military o Commercial o Amateur o Experimental
The applications for SWOCs will typically require the following categories:
· Coverage national or global · Service type FSS · Use case Commercial GA 730640 Page 87 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Technically Satellite communications are mainly classified according to one of three major ways of the satellites orbit above the Earth:
· Geosynchronous Orbit (GEO) which is 35 786 km from the Earth’s surface ;
Satellites placed in this orbit can “stand still” with respect to a specific location on earth. That is, if a viewer on Earth were to look up into the sky and spot a satellite in GEO, it would seem as if it isn’t moving. (Propagation Delay: 250-300 ms for a single hop, from Earth to Earth)
· Medium Earth Orbit (MEO) that ranges from 10 000 to 15 000 Km above the Earth;
(Propagation Delay: 110-130 ms for a single hop)
· Low Earth orbit (LEO) that ranges from 700 to 1 400 Km above the Earth;
(Propagation Delay: 20-25 ms) A satellite in a geostationary orbit (at an altitude of 35 786 kilometres) can "see" the surface up to 81 degrees away from its position. This corresponds to a 17 000 km footprint diameter on the Earth). A more practically useful limit for communications is between 70° N and 70° S parallels. The number of satellites needed for global coverage ranges from 3 to 4. As MEO and LEO are not “stationary” like GEO, more satellites would be needed to obtain complete coverage over a certain area. Typically MEO requires from 10 to 15 satellites and LEO more than 40. In order to limit the MEO satellite scrolling, orbit planes are inclined near 55° to the equator. Several planes generate a Walker constellation, as for GNSS. As consequence, a phased start up is possible only for GEO and MEO. In case of LEO, phase start is possible only region by region. These coverage characteristics have a big relevance in case of railway application. In particular, considering GEO, a drawback is a large link budget (near 200 dB), but many advantages are consequent:
· the link is not subjected to handover; · the elevation angle is high, then the pointing of the antenna requires o minor adjustments, even in mobility, o minor mechanical problems for its assembly and for its life duration.
In case of GEO, the simplification does not stop to the antenna steering mechanism but involves also the mobile terminal that requires lower cost. This is valid also for fixed terminal and moreover point to point connections are possible via a LES (Land Earth Station). Considering the following SATCOM frequencies and their present allocation:
GA 730640 Page 88 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· L-band (1-2 GHz) is allocated for Mobile Satellite Services · C-band (4-8 GHz) for Fixed Satellite Services · X-band (8-12 GHz) for Military/Governmental (Fixed and Mobile services) · Ku-band (12-18 GHz) for Fixed and Broadcast Satellite Services · Ka-band (26-40 GHz) for Fixed and Mobile Satellite Services and Military/Governmental.
Even if there are specific allocations for different regions of the world and different types of services, we can note that L-band is usable for railways application, being allocated for mobile services. This allocation also determines a further simplification of the antenna system in a mobile vehicle. This is particularly relevant if we consider the criticality of a mechanical assembly on the roof of a locomotive in railway application. But an attractive perspective should be to spare any mechanical steering device, with static antennas.
6.3.5.1. GEO L-band satellite services application for Railway Signalling Concerning already existing application of GEO satellite based communication, it is worth to mention the “Train Integrated Safety Satellite System (3InSat) Demonstration project”, funded by ESA in the ARTES 20 IAP programme, This project ran from 2012 to 2015 and was led by Ansaldo STS. This application integrated different space assets, such as Satellite Communication and Satellite Navigation with Railway Signalling, based on ERTMS standard, proving and testing the final solution in a real operating environment, constituted by the Sardinia regional railway line of RFI in Italy. One of the most relevant 3InSat objective was the new TLC paradigm introduced, consisting in a multi-bearer approach that uses a combination of existing public mobile networks (2G/3G) with satellite communication, in alternative to GSM-R based TLC network. Concerning SATCOM, 3InSat adopted the communication over the satellite backhaul link using the Inmarsat’s Broadband Global Area Network (BGAN) commercial service based on geo- stationary constellation with a global coverage. The choice in 3InSat considered also that:
· BGAN meets military and government requirements for security and supports all major VPN products and encryption standards. · as already mentioned for GEO in general, BGAN is available across the globe, with the exception of the extreme polar regions. · BGAN services are delivered via the Inmarsat-4 network, with 99,9 % satellite and ground network availability and an operational lifespan expected into the 2020s.
GA 730640 Page 89 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
From the throughput point of view, a single BGAN terminal provides simultaneous voice and broadband data up to 492 kb/s, enabling simultaneous voice and data. In particular, BGAN supports a range of guaranteed on-demand streaming IP rates from 32 kb/s to at least 384 kb/s, and up to 450 kb/s with BGAN X-Stream™. The last one special streaming service could be helpful to avoid video or audio drop outs.
In the on-board side of 3InSat, the satellite BGAN terminal was connected to a steerable L-Band antenna on the roof of a train, travelling along a real operational railway line, and providing radio access to the forward and reverse link of the satellite. Tests were performed on the RFI lines in Sardinia connecting Cagliari and Olbia (about 300 km) and with a speed up to 130 km/h. Two trips per day each lasting 3h 50m each way, have been performed for all the duration of the test campaign to get a significant set of experimental data. This railway line is quite representative of typical operational scenarios such as the urban, sub- urban and rural environment and the train has collected 23 days of data for a cumulated travelled distance of 13 800 Km. The outcomes demonstrated that the throughput performances of the Inmarsat’s BGAN commercial service is widely suitable to fulfil this railway scenario.
6.3.5.2. GEO S-band prototype services for buses and trucks SAFETRIP was a FP7 project co-funded by EC, started on January 2009 and achieved on April 2013. Its consortium was composed of 20 partners, led by SANEF (Société des Autoroutes du Nord et de l’Est de la France, the 4th highway operator in Europe). EUTELSAT & DLR were involved for the satellite telecom payload and the hub station. ABERTIS and EUROLINE were participants on the user side. The cooperation of SANEF with MASTERNAUT was increased and took profit from the relations with the insurance company IMA (Inter-Mutuel Assistance). INDRA was in charge of architectural design, and of a critical part of the project: the satellite return link system development and validation. SAFETRIP has explored new opportunities and innovative ITS services to be delivered to passenger cars, trucks and bus drivers. Also some services were designed to improve safety and help highway patrol staff in their current activities. A cooperation of Satcom services and Cellular terrestrial services has been investigated. Mobile Satellite System (MSS) from GEO has been retained, in S-band in order to optimize the solutions for antennas. EUTELSAT 10 (previously W2A) in 10°E longitude and the transponder installed by ALCATEL Space at 2,2 GHz was used for the proof of concept. From the beginning, this S-band payload was intended to deliver mobile multimedia broadcast services (Mobile TV, digital
GA 730640 Page 90 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models radio...) directly onto user terminals over key markets in Western Europe. Secure communications and crisis management support was targeted as well. The main innovation of W2A S-band payload was the large unfurlable antenna (12 m diameter) excited by a sophisticated MBA source provided by HARRIS. Such an antenna was experimented before in the USA with ICO G1 (launched on April 2008). More than 60 dBW of EIRP were expected ! Six bidirectional spot beams have been defined in order to cover Europe as a puzzle. Six forward and twelve return channels of 5 MHz width are supported. For the OBU, only dipole antennas on the roof of the vehicles were considered. The link budget of 193 dB was theoretically validated. But a problem arised during W2A installing in orbit, and one of the 6 arms of the MBA source did not fully unfold. Consequently, a penalty of about 3 dB was suffered on EIRP and on G/T, and the beams have been reconfigured to cover only 2 spots over France territory. Nevertheless, this is a significant prototype of future S-band services to mobiles. For SAFETRIP, downlink software involves encapsulating near real-time messages, short messages and traffic broadcast into DVB-SH (Satellite to Handheld) streams using MPEG2-TS over OFDM. Uplink uses Enhanced ALOHA and Spread Spectrum access with 1200 byte packet size and 10 kb/s bit rate. Up to 600 parallel connections are possible using CDMA, i.e. the global maximum throughput should be 2,2 Mb/s per 5 MHz wide channel. Now S-MIM (S-band Mobile Interactive Multimedia) protocols are an ETSI standard [N4]. Notice that S-band services to mobiles have been introduced by SOLARIS Mobile, a joint venture of SES and EUTELSAT. At the same time as EUTELSAT 10E failed, the EC granted to SOLARIS and INMARSAT only the right to operate such Mobile Satellite Services (MSS) in Europe. In March 2015 SOLARIS, which still controls 10E access, became EchoStar Mobile. On its side, INMARSAT is preparing S-band services from HELLAS 3 geosynchronous satellite, built by Thales-Alenia Space for ARABSAT (to be launched in 2017). 25 of 28 European Union (EU) states have issued S-band licenses for the previous EuropaSat project which is now replaced by HELLAS 3.
6.3.5.3. New LEO services from IRIDIUM, GOOGLE and alternatives The main objectives are taking profit from better link budgets, due to shorter distances to the Earth. Moreover antenna gains increase at higher frequencies, at both ends, especially at satellite end. So using higher frequencies for shorter distances make it feasible to use sectorial fixed antenna for mobiles. Regarding services, an objective is to be compatible with 4G and 5G cellular
GA 730640 Page 91 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models networks, as BGAN was designed to be compatible with 3G (IMT-2000/UMTS) using INMARSAT IV GEO.
6.3.5.3.1. IRIDIUM IRIDIUM traditionally was focused on voice service to handheld terminals, with a non- directive compact antenna, mainly for governmental use, anywhere over the Earth. IRIDIUM is now gaining approximately half of its new subscribers from M2M market. This sector is going to be a fundamental part of its business, with an 18 percent increase over last year, compared to a 3 percent year over year increase in commercial voice and data. The company’s government business is also seeing improvement, increasing 11 percent from the same time last year. IRIDIUM has two contracts with the United Sates’ Defense Information Systems Agency (DISA) as well as a $38 million contract for supporting the Department of Defense‘s (DoD) dedicated gateway. IRIDIUM is working for its upcoming constellation, Iridium NEXT. Thales Alenia Space has completed the Main Mission Antennas (MMAs), for which one goes on each NEXT satellite. On 2014, Iridium selected Radisys’ T-Series Commercial Off-The-Shelf (COTS) platforms to upgrade the ground station infrastructure for NEXT, and support the so-called Certus service. AssetLink Global, a Machine-to-Machine (M2M) and Internet of Everything (IoT) solutions provider, has got a partnership with IRIDIUM to connect its AssetPack 3 solar rechargeable monitoring and tracking device. According to IRIDIUM, the partnership will improve AssetLink’s end-to-end asset management for customers in remote areas, even for High Data Rate (HDR) communications. NEXT will be compatible with 4G cellular systems. But an IOI (In Orbit Infrastructure) with direct trunking between satellites, will not make easy the migration to 5G and other systems. Iridium planned to launch its first two NEXT satellites in mid-2015 on a Dnepr rocket, but the launch faced a problem because the Dnepr rocket is Ukrainian-manufactured and fired from Russian soil. The serial satellites is being launched by SpaceX (10-12 satellites per launch). The constellation provides L-band data speeds of up to 1.5 Mbit/s and High-speed Ka-Band service of up to 8 Mbit/s.
6.3.5.3.2. GOOGLE GOOGLE has an ambitious project, Loon, based on stratospheric airships. The balloons intend to float in the stratosphere, twice as high as airplanes and the weather. In the stratosphere, there are many layers of wind, and each layer of wind varies in direction and speed. Loon balloons go where they’re needed by rising or descending into a layer of wind blowing in the desired direction of travel. By partnering with Telecommunications companies to share cellular spectrum GOOGLE
GA 730640 Page 92 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models enables people to connect to the balloon network directly from their phones and other LTE- enabled devices. The signal is then passed across the balloon network and back down to the global Internet on Earth. Project Loon began in June 2013 with an experimental pilot in New Zealand, where a small group of Project Loon pioneers tested Loon technology. Each balloon can provide connectivity to a ground area about 40 km in diameter using LTE wireless communications. To do that, Project Loon partners with telecommunications companies to share cellular spectrum so that people will be able to access the Internet everywhere directly from their phones and other LTE-enabled devices. Balloons will relay wireless traffic from cell phones and other devices back to the global Internet using high data-rate links. A need of thousands balloons is anticipated to cover efficiently regions far away from any infrastructure. GOOGLE has settled its balloon assembling own factory and is now able to produce a balloon within few hours. There was a joint US-France pioneer project, STRATCOM, in which CNES and EADS were involved. On 2002, STRATCOM has established that a serial big airship (equipped with 2 Rotax engines) and its telecom payload based on PMR (TETRA) could cost under $2 Millions. Large gain antennas were possible for higher bit-rate, because the inside skin of the top of balloon could be metallized and used as a big reflector. A fleet of 13 airships was estimated to cover the US territory. Maintenance cycle –with a return to ground facilities– should be more than one year.
6.3.5.3.3. Airbus Defence and Space Airbus Defence and Space aims to establish a major presence in the growing market of the Internet of Things (IoT). Airbus D&S launched the Mustang project with a consortium comprised of CEA-LETI, SYSMECA and SIGFOX, the latter of which raised $ 115 million from investors earlier for a low-energy global cellular IoT network. The three-year Mustang project is developing the technology necessary to create a hybrid IoT system that, emanating from France, would grow to connect the globe with an integrated, low-cost short message service. Airbus D&S anticipates a trend toward global networks able to connect directly many small and low power objects. Due to cost and energy constraints, a narrowband system with small, cheap and highly autonomous terminals is going to be a key market enabler in the next years. The Mustang project is partially funded by France’s Future Investments Program (PIA), which the General Investment Commission (CGI) and the French Minister of Economy, Industry and Digital Affairs run jointly. The project involves the development of the terminal’s modem chipset, the optimization of communication protocols and the validation of the system through an aircraft application demonstration. Airbus Defence and Space, the company that launched the Mustang
GA 730640 Page 93 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models program and is leading much of the satellite side, is investing the 70 percent of the budget on its own. The system will use a dual-mode satellite-terrestrial terminal to switch automatically, with satellite links using a distinct communication protocol and connections to the SIGFOX terrestrial network using the 868 and 915 MHz Industrial, Scientific and Medical (ISM) bands. SIGFOX uses a UNB (Ultra Narrow Band) based radio technology to connect devices to its global network. The use of UNB is key to providing a scalable, high-capacity network, with very low energy consumption, while maintaining a simple and easy to rollout star-based cell infrastructure. Satellite will be largely addressed to cover isolated areas beyond the reach of terrestrial communications, as well as for backup to critical applications or to fill in when terrestrial networks are down. Three main operation domains appear as the most valuable from the market studies: logistics, maintenance and security, to serve business and governmental needs. Maritime, energy, and aviation are highlighted markets. The objective is to get a full and global network deployed and the bi-mode service running, with a few hundreds of thousands of compatible terminals deployed on the field in 2020. Some of IoT things sit in factories or in consumers’ homes, but others are situated up far from conventional networks or power sources. For example, sensors on mines, pipelines, rigs or tankers can report on current conditions on site, and tiny radios attached to enterprise assets or goods in transit can show where they are. Many rely on batteries that have to last years. Airbus D&S has identified the need for a very cost-efficient, flexible radio processor at the satellite level. The company is developing such a processor, based on prior work within the IoT that is expected to serve many applications. The company is also working on the user-integrated, bi- mode communication module, which is optimized in terms of communications protocols to operate with very low power equally for satellite. The ability to communicate with a satellite in Low Earth Orbit (LEO), over typically 1000 kilometers, has actually been demonstrated early this year in a demo using the Airbus-developed Spot 7 satellite. With LEO, latency can be controlled under 10 ms. Moreover, the feasibility of Laser direct links between LEO and GEO has been proven before via LIOPT and LOLA projects, led by ASTRIUM.
6.3.5.3.4. ORBCOMM ORBCOMM’s acquisitions of SkyWave and InSync bring to eight the number of acquisitions it has conducted since 2011. SkyWave, formerly Inmarsat’s largest reseller in the Machine-to-Machine (M2M) market, was Orbcomm’s biggest acquisition of the eight, for $130 million. ORBCOMM is now the largest M2M service provider on Inmarsat’s L-band satellite network, with an estimated GA 730640 Page 94 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models annualized $ 60 million in revenues. Through its Merger and Acquisition (M&A) activity, ORBCOMM has transformed from mainly focusing on satellite connectivity to including device management, customized hardware, and applications. ORBCOMM is looking for partnerships with other satellite companies such as GLOBALSTAR and INMARSAT. ORBCOMM and INMARSAT (hereafter) are currently working together on modems. Through SkyWave, ORBCOMM will also be able to leverage its IsatData Pro (IDP) solution, which is jointly owned with INMARSAT, and enter new markets such as Eastern Europe and parts of Asia. With OG2 (ORBCOMM Generation 2) service activated ORBCOMM is strategizing on ways to bring more satellite services to M2M, rising to be one of the market’s main competitors.
6.3.5.4. New GEO services
6.3.5.4.1. Global Xpress Coming back to GEO with INMARSAT, the new Global Xpress (GX) satellite network is a $1,6 billion investment with an expectation of annual revenues of $ 500 million from the fifth anniversary. The first GX satellite was launched in December 2013, and the second satellite in February 2014. Following this, the failure of a Federal Proton mission introduced a significant delay in achieving global services. Still, INMARSAT has signed customers on GX, of which one notable capacity buyer is the US government. The US government is particularly interested in global Ka-band and the unique military Ka-band capabilities brought by GX. Aviation is a top market for GX. INMARSAT now has approval from 11 countries for the ground component of its European Aviation Network. In partnership with Honeywell, INMARSAT is working with Kymeta on a lightweight antenna specifically for the business and commercial aviation market. GX will be compatible with the hybrid system comprised of the EuropaSat (now HELLAS 3) S + Ka resources and an Air-to-Ground (ATG) component.
6.3.5.4.2. BATS Notice that an ambitious EC FP7 project was launched in 2012 and has been concluded in 2016: Broadband Access via integrated Terrestrial and Satellite Systems (BATS). High bit rate from 30 Mb/s to 1 Gb/s are targeted, using Ku band (12-14 GHz) and Ka band (40 GHz) to and from three existing ESA satellites: Artemis, HYLAS1 & HYLAS2. They are GEO satellites, so that latency is about 300 ms for one hop. The innovative ‘highly adaptable’ payload was developed by Airbus D&S, with the assistance of ESA’s Advanced Research in Telecommunication Systems (ARTES) programme. ESA has devoted years to developing satellite broadband technologies through ARTES, and now several of these innovations are being put to work on HYLAS Satellites (HYLAS3 & HYLAS4 are expected shortly).
GA 730640 Page 95 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 6.4. Communication Security
This chapter has been taken over and adapted from the NGTC project [4].
6.4.1. General information
For the class of systems of railway applications , the IEC 62443 standard sets [40] is proposed as sets of technical recommendations to provide end-to-end security. The ISO 15408 (Information technology – Security techniques – Evaluation criteria for IT security) [41] as Common Criteria for security analysis and its certification is consistent as well. Traditionally, a hierarchical structure is considered, as shown below:
Applications & Management
OSI upper Information Information protection Layers protection INFOSEC
OSI L3 Encryption Decryption
Access Access + encoder + decoder
OSI L2 COMSEC
Modulation Demodulation OSI L1
Waveform Waveform TRANSEC
Physical channel and media
Figure 6.3 – Hierarchical structure
· INFOSEC (INFOrmation SECurity) is at applicative level; INFOSEC takes into account upper OSI layers and applications. INFOSEC is not within the scope of WP6. But with the International Common Criteria, a trend is to globalize INFOSEC and COMSEC. · COMSEC (COMmunication SECurity) is at network level.
COMSEC includes TRANSEC, crypto security and emission security, with the following definitions:
· TRANSEC (TRANsmission SECurity): at transmission (data link) and physical level: GA 730640 Page 96 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
o Transmission Security is the component of security that results from the application of measures designed to protect transmissions from interception and exploitation by means other than cryptanalysis: e.g. frequency hopping, spread spectrum, UWB and frequency chirp. o Physical security is the component of security that results from all physical measures necessary to safeguard classified equipment, material, and documents from access thereto or observation thereof by unauthorized persons. · Crypto security: The component of communications security that results from the provision of technically sound cryptosystems and their proper use. This includes ensuring message confidentiality and authenticity. · Emission Security : The protection resulting from all measures taken to deny unauthorized persons information of value that might be derived from communications systems and cryptographic equipment intercepts and the interception and analysis of compromising emanations from cryptographic—equipment, information systems, and telecommunications systems.
6.4.2. IPSec as COMSEC for the internet
IPSec (Internet Protocol Security) results from the application of COMSEC principles to Internet world. But IPSec does not contain any TRANSEC facility. When using IP v6, TRANSEC could be enforced only by transmission technologies, i.e. vectors themselves. IPSec is a protocol suite for secure Internet Protocol (IP) communications by authenticating and encrypting each IP packet of a communication session [49]. IPsec includes protocols for establishing mutual authentication between agents at the beginning of the session and negotiation of cryptographic keys to be used during the session. IPsec can be used in protecting data flows between a pair of hosts (host-to-host), between a pair of security gateways (network- to-network), or between a security gateway and a host (network-to-host). Internet Protocol security (IPsec) uses cryptographic security services to protect communications over IP networks. IPsec supports network-level peer authentication, data origin authentication, data integrity, data confidentiality (encryption), and replay protection. IPSec implies the negotiation of a set of security parameters such as cryptographic algorithms or key material. The negotiation itself should be secured so that any attack is unable to access to the algorithms and to the keys. IETF has designed the Internet Key Exchange protocol (IKE v2) for doing that. The security enforcement provided by IKE v2 is of vital importance to protect IPv6 communications. The initiator starts the IKE v2 protocol whereas the responder acts as a server during the negotiation. GA 730640 Page 97 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Encryption shall be used for signature and authentication, but also should be used for data protection. Notice that it is possible to change the conventional encryption process and procedures of IPSec to more sophisticated ones. In such a case, the basic rule is to equally focus on: 1. the quality and the efficiency of the algorithm (using adequate HW platform); 2. the performances of the key generation and distribution system; 3. the crypto-period of the system, that must be matched to 1 and 2; 4. the security policy and the accreditation of human operators which shall be related to the security objectives. More security rules can be considered, such as not to expose encrypted traffic to listening on a large scale. For instance in the past, governmental encryption was strictly avoided over INMARSAT, which is listened by a lot of people in the world. In summary IPSec is a good feature to ensure Authentication of the IP address of the sender and the Integrity and Confidentiality of the transmitted messages at IP level when and where It is not provided by the radio vector itself.
6.4.3. Security for Railways
IEC 62443 and ISO 15408 standards are generic and quite high level, therefore they are not specific to signalling applications. The deliverable "Cyber-security roadmap for PTOs" of the European project SECUR-ED presents the security standards, best practices and recommendations applicable for the different subsystems involved into the Public Transportation infrastructure. Among other applications to Railways, the CBTC system for Urban Rail is classified into the Industrial automation and control systems. Note that SECUR-ED recommendations have been taken into account by a parallel project PROTECTRAIL focused on Mainline (FP7 project completed on May 2014). The current applicable standard for railway in the field of communication is the EN 50159 "Railway Applications - Communication, Signalling and Processing Systems – Safety Related Communication" which covers mainly safety but also partially security. Indeed, the introduction of that standard is quite clear in defining what it is covering and what it is not covering:
· It gives the basic requirements needed to achieve a safety-related communication between safety related equipment using a transmission system which was not necessarily designed for that.
GA 730640 Page 98 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· It is therefore taking into account intentional attacks by means of messages to safety- related applications · But it doesn't cover general communication security issues.
The study presented below covers both aspects. As recommended in IEC 62443 standard, it starts by identifying the risks introduced by the use of a communication system. The following list of general technical risks is identified in the standard EN 50159 regarding the Safety-related messages:
· Repetition of message · Deletion of message · Insertion of message · Re-sequencing of two or more messages · Corruption of message · Delay of message · Masquerade (a masquerade is a type of attack where the attacker pretends to be an authorized user of a system in order to gain access to it or to gain greater privileges than they are authorized for).
A specific risk analysis should be conducted in any case for each project to complete that general list if needed.
Generally known communication attacks listed below are leading to one risk above:
· Jamming (jamming is risk that a signal from an external device being sent to all other devices resulting into loss of messages); · Intentional overload of the system; · Spoofing and redirection of messages to other destination (Spoofing refers to a low-level attack which attempts to mislead the provided information to the receiver. This is done by broadcasting not counterfeit data signals or genuine “corrupted” signals captured and modified in a different source of information. The security issues behind spoofing attacks are normally related to the malicious modification of the provided information in a way that the source is affected); · Penetration into the communication system by an attacker stopping the transmission system.
EN 50159 defines requirements for the safety-related application messages as efficient measure against repetition, insertion, re-sequencing and delay, based on sequence number, timestamps and safety code. These measures are obviously applied at application level or transport level but
GA 730640 Page 99 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models are not relevant for the IP Comm system itself. They don't prevent the attack itself but ensure that the application will have a fail-safe reaction by detecting the attack. In addition the safety code is not a cryptographic code and is not sufficient to prevent an attacker creating messages with correct timestamp, sequence number and safety code (in order to do that, access to detailed specification of the signalling application is required). This is the reason why EN 50159 also requires preventing masquerade by using cryptographic techniques to ensure authentication of the senders. Whilst not directly part of EN 50159 standard, confidentiality is known as important to reduce the knowledge of any attacker and therefore avoid that he knows how to direct his attack efficiently.
Last but not least, it has to be noted that the signalling applications are designed to react safely in case of loss of communication by stopping the trains (due to message deletions, deny of service or any other reasons); if a train is stopped in inter station, there is always a risk that passengers try to leave the train after a while (it could be dangerous to disable completely the possibility to open the doors in that case) and be injured by electrical power or running trains. Therefore it appears that the availability of the communication system of Signalling applications is essential to safe railway operations.
All this can be summarized in the following table, highlighting the requirements for the IP Comm system:
Risk Detection means in Mitigation measure in IP Comm Comment Signalling application as system requested by EN50159
Repetition of Sequence number (to Authentication of IP addresses, IP Comm system design messages detect the issue and and securisation of the control should minimize this risk, to have fail safe reaction: plane3, to avoid a "Man in the avoid fail safe reaction discard the message) middle"
Deletion or loss Sequence number, time of messages stamp and timeout (to Redundancy/diversity of detect the issue and transmission means have fail safe reaction
3 Control plane is used to describe all the signalling data and internal protocol to manage the IP Comm system itself. GA 730640 Page 100 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Risk Detection means in Mitigation measure in IP Comm Comment Signalling application as system requested by EN50159
such as : retransmission of the loss message)
Insertion of Sequence number (to Authentication of IP addresses, IP Comm system design messages detect the issue and securisation of the control plane, should minimize this risk, to have fail safe reaction) to avoid a "Man in the middle" avoid fail safe reaction
Re-sequencing Sequence number (to Authentication of IP addresses, IP Comm system design of messages detect the issue and and securisation of the control should minimize this risk, to have fail safe reaction) plane, to avoid a "Man in the avoid fail safe reaction middle"
Corruption of Safety code Integrity protection : error Safety codes are efficient messages detection and cryptographic only up to a given rate of Integrity code (to detect techniques corrupted messages, the issue and have fail therefore, when too many safe reaction : discard corrupted messages are the corrupted message) received, the application is falling in a fail-safe defense state. That's why It is recommended that the IP Comm system avoid to transmit too many corrupted messages by using an integrity code
Delay of Timestamp/timeout Limited latency and jitter, to messages avoid fail safe reaction
Masquerade Identification of sender Authentication of the IP addresses, securisation of Authentication of sender control plane, firewalls. /
Deny of Service Reliability of the communication system (redundancy – diversity)
Table 6.18 – Detection means and mitigation measures to limit security risks
GA 730640 Page 101 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
As a conclusion, the requirements given to IP Comm systems regarding security and safety are therefore the following:
· Identification/Authentication of the IP addresses; · Securisation of the control plane; · Integrity of the transmitted messages · Availability of the communication (through redundancy – diversity); · Limited latency and jitter.
Due to the fact that the communication system is not a Safe System, the signalling application has to implement the counter measures described above.
In terms of technical measures to ensure security, the IP Comm System will be able to implement COMSEC, as conventionally defined:
· The security of the information itself, especially its storage or usage, is dealt at upper levels and is out of the scope of the IP Comm System; · The security of the software, including the one of the IP Comm System itself should be ensured at upper levels.
After this overview of the technical mitigation measures allocated to the IP Comm System, the existing features embedded in each selected vector are described hereafter.
6.4.4. Existing Communication security features in LTE
6.4.4.1. Security overview The LTE security architecture is defined by the 3GPP's TS 33.401 standard. The following figure gives an overview of the overall security architecture applied in LTE networking solution:
Figure 6.4 – Security architecture in LTE GA 730640 Page 102 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
ME: Mobile Equipment AN: Access Network (eNodeB like) SN: Serving Network (EPC like) HE: Home Environment (HSS/AuC like) USIM: UMTS Subscriber Identity Module Five security feature groups are basically defined. Each of these feature groups meets certain threats and accomplishes certain security objectives: · Network access security (I): the set of security features that provide ME (can be users or On Board Unit device) with secure access to services, and which in particular protect against attacks on the radio access link. · Network domain security (II): the set of security features that enable nodes to securely exchange signalling data, user data (for example with an IPSec tunnel between eNodeB & S-GW), and protect against attacks on the wireline network. · User domain security (III): the set of security features that secure access to mobile stations, with user authentication via PIN code validation and Mobile Equipment control by USIM. · Application domain security (IV): the set of security features that enable applications in the user and in the provider domain to securely exchange messages. · Visibility and configurability of security (V): the set of features that enables the user to inform himself whether a security feature is in operation or not and whether the use and provision of services should depend on the security feature.
Basically the LTE components mainly involved in security are: · The Mobile Equipment (ME) hosting SIM card and responsible for running application (USIM) · The eNodeB being part of the air interface (UU) protection · The Mobility Management Entity (MME), controlling the authentication functions · The Home Subscriber Server (HSS) hosting user identifiers and critical security information
6.4.4.2. Concept of separation of the communication planes The LTE uses two planes of communication: one control plane and one distinct user plane multiplexed in one single RF signal and then routed towards different destinations in EPC (MME for Control Plane & S-GW for User Plane) Two types of signalling messages are exchanged over the LTE systems and are illustrated bellow.
GA 730640 Page 103 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Figure 6.5 – Signalling messages in LTE
· The Radio Resource Control (RRC) protocol layer is part of air interface control plan and exists in UE & eNodeB. The main services and functions of the RRC sublayer include: o Establishment, maintenance and release of an RRC connection between the UE and E-UTRAN; o Security functions including key management; o Establishment, configuration, maintenance and release of point to point Radio Bearer; o NAS (Non-Access Stratum) direct message transfer to/from NAS from/to UE etc. · The Non-Access Stratum is a set of protocols, part of control plane and used to convey non-radio signalling between UE & MME. The main functions of the protocols that are part of the NAS are the support of mobility of UE and the support of session management procedures to establish and maintain IP connectivity between UE & PDN-GW. The list of requirements on EPC and E-UTRAN building blocks related to keys are illustrated bellow.
GA 730640 Page 104 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Figure 6.6 – EPC and E-UTRAN Building blocks
The key hierarchy includes the following keys: KeNB, KNASint, KNASenc, KUPenc, KRRCint and KRRCenc.
6.4.4.3. Security mechanism The current IT security features are implemented at the following LTE subsystems: · SIM cards · Air Interface Protection (performing user-to-network security) · IP Backhaul Protection
6.4.4.3.1. About the SIM cards
The SIM card stores the sensitive information containing:
· Pre Shared Key (K) - 128-bit master key put into USIM and HSS by carrier · IMSI The SIM card performs the cryptographic operations for authentication.
6.4.4.3.2. About the Air Interface Protection
Basically the different involved users to network security mechanisms are defined as follows.
The connection between the UE and the eNodeB is referred to as the air interface. About the Air Interface Protection, two algorithms exist to protect this air Interface:
GA 730640 Page 105 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· SNOW 3G : stream cipher designed by Lund University (Sweden) · AES : Block cipher standardized by NIST (USA) Each algorithm can be used for confidentiality protection, integrity protection, or to protect both.
· User identity and device confidentiality The IMEI (International Mobile Equipment Identity) shall be securely stored in the terminal and not sent to the network before the NAS security has been activated.
· Entity authentication Entity authentication is as defined by TS 33.102 subclause 5.1.2. User data and signaling data confidentiality is done according to the standard 3GPP TS 33.401 - 5.1.3. The RRC confidentiality protection is provided by the PDCP (Packet Data Convergence Protocol) layer between UE and eNodeB. Ciphering may be provided to RRC signaling to prevent UE tracking based on cell level measurement reports, handover message mapping, or cell level identity chaining. RRC signaling confidentiality is an operator option.
The NAS signaling may be confidentiality protected. NAS signaling confidentiality is an operator option.
The input parameters for the NAS 128-bit ciphering algorithms shall be the same as the ones used for NAS integrity protection as described in clause 8.1, with the exception that a different key, KNASenc, is used as KEY.
For railway applications, the RRC & NAS signaling confidentiality protection should be used. The User plane data confidentiality protection shall be done at PDCP layer between the UE and the eNodeB and is an operator option.
For railway applications, the User plane confidentiality protection should be used The confidentiality protection for RRC and User plane is applied at the PDCP layer, and no layers below PDCP are confidentiality protected.
The confidentiality protection for NAS is provided by the NAS protocol.
· User data and signaling data integrity is done according to the standard 3GPP TS 33.401 - 5.1.4 GA 730640 Page 106 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
The Integrity protection, and replay protection, shall be provided to NAS and RRC-signaling. The RRC integrity protection shall be provided by the PDCP layer between UE and eNodeB and no layers below PDCP shall be integrity protected.
The Integrity protection for NAS signaling messages shall be provided as part of the NAS protocol. The standard 3GPP TS 33.401 - 5.1.4 does not design any integrity protection for the User Plane. Consequently the User Plane packets between the eNodeB and the UE should be integrity protected at the Application Layer to mitigate this potential security breach. The security requirements on eNodeB can be split into 2 parts: · With the requirements for handling User plane data for the eNodeB (according to the standard 3GPP TS 33.401 - 5.3.4)
It is the eNodeB task to cipher and decipher User plane packets between the Uu reference point and the S1/X2 reference points.
The User Plane data ciphering/deciphering shall take place inside the secure environment where the related keys are stored.
The transport of user data over S1-U and X2-U shall be integrity, confidentially and replay protected from unauthorized parties. If this is to be accomplished by cryptographic means, clause 12 of the standard shall be applied.
The use of cryptographic protection on S1-U and X2-U is an operator's decision. For Railway applications, it should be adopted to protect the User Plane data of the eNodeB.
In case the eNodeB has been placed in a physically secured environment then the 'secure environment' may include other nodes and links beside the eNodeB. · With the requirements for handling Control plane data for the eNodeB (according to the standard 3GPP TS 33.401 - 5.3.4a)
It is the eNodeB's task to provide confidentiality and integrity protection for control plane packets on the S1/X2 reference points.
The Control plane data ciphering/deciphering shall take place inside the secure environment where the related keys are stored.
The transport of control plane data over S1-MME and X2-C shall be applied to integrity-, confidentiality- and replay-protected from unauthorized parties. If this is to be accomplished by cryptographic means, clause 11 of the standard shall be applied. GA 730640 Page 107 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
The use of cryptographic protection on S1-MME and X2-C is an operator's decision. For Railway, it should be adopted to protect the Control Plane data of eNodeB. In case the eNodeB has been placed in a physically secured environment then the 'secure environment' may include other nodes and links beside the eNodeB. About the Security Procedures between UE and EPC Network Elements (MME & HSS):
· The Authentication and Key Agreement (AKA) is the protocol used by the devices to authenticate with the carrier network. · The 3GPP 33.401 -6.1.1 standard defines the authentication and key agreement procedure that is used over E-UTRAN. In a first step the AKA protocol performs authentication mechanism as illustrated below:
Figure 6.7 – Authentication mechanism of AKA
After the completion of the AKA protocol the cryptographic keys used to encrypt the calls are derived. The AKA protocol shall produce keying material forming a basis for user plane (UP), RRC, and NAS ciphering keys as well as RRC and NAS integrity protection keys.
6.4.4.3.3. About the IP Backhaul Protection
Basically the confidentiality protection of traffic for both control and user planes running over the S1 Interface is performed by the use of hardware security appliances called Security Gateways (SEG) designed at the EPC front. The protection uses IPSEC tunnel created between the eNodeB’s and the SEG.
· Network Domain (IP Backhaul) Control Plane protection (between E-UTRAN and EPC)
GA 730640 Page 108 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
The protection of IP based Control Plane signalling for EPC and E-UTRAN is done according to the 3GPP TS 33.401-11 standard.
In order to protect the S1 and X2 control plane, it is required to implement IPsec ESP according to RFC 4303 as specified by TS 33.210. For both S1-MME and X2-C, IKEv2 certificates based authentication according to TS 33.310 shall be implemented. For S1-MME and X2-C, tunnel mode IPsec is mandatory to implement on the eNodeB.
On the core network side a SEG may be used to terminate the IPsec tunnel. In case control plane interfaces are trusted (e.g. physically protected), there is no need to use protection according to TS 33.210.
· Network Domain (IP Backhaul) User Plane protection (between E-UTRAN and EPC)
The protection of IP based User plane for EPC and E-UTRAN is done according to the TS 33.401- 12 standard.
The protection of user plane data between the eNodeB and the UE by user specific security associations is covered by clause 5.1.3 and 5.1.4.
In order to protect the S1 and X2 user plane as required by clause 5.3.4, it is required to implement IPsec ESP according to RFC 4303 as profiled by TS 33.210, with confidentiality, integrity and replay protection.
The tunnel mode IPsec is mandatory to implement on the eNodeB for X2-U and S1-U.
On the core network side a SEG should be used to terminate the IPsec tunnel for the User Plane protection.
For both S1 and X2 user plane, IKEv2 with certificates based authentication shall be implemented.
In case S1 and X2 user plane interfaces are trusted (e.g. physically protected), the use of IPsec/IKEv2 based protection is not needed.
· Management plane protection over the S1 interface
The Management plane protection over the S1 interface is done according to the standard 3GPP TS 33.401 -13.
GA 730640 Page 109 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
The Clause 5.3.2 requires that eNodeB setup and configuration traffic, i.e. the management plane, is to be protected between the EPS core and the eNodeB. This traffic is typically carried over the same backhaul link as the S1 interface. Therefore, the protection mechanism defined for S1-MME and S1-U may be re-used for S1 management plane, S1-M.
In this case and in order to achieve such protection, it is required to implement IPsec ESP according to RFC 4303 as profiled by TS 33.210, with confidentiality, integrity and replay protection.
Tunnel mode IPsec is mandatory to implement on the eNodeB for supporting the S1 management plane.
On the core network side a SEG shall be used to terminate the IPsec tunnel for the Control Plane protection.
For the S1 management plane, IKEv2 with certificates based authentication shall be implemented on the eNodeB.
In case the S1 management plane interfaces are trusted (e.g. physically protected), the use of IPsec/IKEv2 based protection is not needed
Communication Security features Conclusion for LTE
Identification/Authentication Included Securisation of the control plane Included
Integrity of messages Included for control plane, not for user plane
Confidentiality of messages Included for control plane, not for user plane
Availability of the communication To be addressed at the architecture level
Table 6.19 – Conclusion for LTE
6.4.5. Existing Communication security features in 802.11 family and variants
This section first checks what is embedded in general into 802.11 standard family regarding security before checking the situation of 802.11p.
GA 730640 Page 110 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
It has to be clearly indicated at this level that 802.11 is defining the radio airgap only at lower OSI layers (up to layer 2). It is therefore only a subset of the complete IP Comm system as it doesn't include in particular the IP-based trackside network and the On-board network.
· Confidentiality
Confidentiality within 802.11 is achieved by the usage of WPA2. When used with CCMP protocol (based on AES) for the encryption, it is considered secured (with conditions on pass phrase length in case of Pre-shared key) As in any cryptographic protocol, the difficult point is the distribution of the cryptographic materials (pass phrase, keys or certificate). A same pre-shared key installed on all radios (wayside and on-board) can be used, but it should be stored securely and should be changed simultaneously in all communication devices in case of one device considered not secured (lost or stolen for example). A mode using EAP authentication toward a Radius server is also available, with several EAP authentication protocols. It allows to use a different certificate for each AP and so have an easier way to revoke a stolen or compromised device, but implies more traffic on the wayside infrastructure (for AP) and on the Airgap (for on board devices needs). It provides confidentiality only on the Airgap as it works between 802.11 devices only, but it has impact on communication performances as additional exchanges are required between a 802.11 client and an AP before the link is completely established and available for transmission of data (See Appendix 2).
· Specificity of 802.11p 802.11p is part of 802.11 and consequently shares its physical characteristics. Nevertheless some options had been introduced, in particular a mode of transmission "outside of a BSS" which must be used by an ITS station. In that mode, currently mandatory using the 802.11 standard in the 5,9 GHz band in Europe (G5), the following features of 802.11 are excluded:
· Association services · Access control and data confidentiality services It means that with the current state of regulations, WPA2 could not be used in Europe for critical applications over G5.
GA 730640 Page 111 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Even if data confidentiality can be ensured at higher level, and in particular using IPSec tunnel, the fact that any device using 802.11p could be received by a CBTC Access point opens the door for a spoofing attack.
· ITS Security: Privacy protection and access control Due to the fact that 802.11p has been introduced as the main communication vector between ITS applications, the way the ITS sector plans to take into account the security issue has to be checked to see what could be re-used or not, in line with that specific technology.
With 802.11p, there is no significant TRANSEC, and possibly no IPSec at all in the direct mode (V2V) which is largely spread for ITS. The ITS sector is actively developing security measures in INFOSEC area, mainly in the field of authentication and third party certification using PKI [50] [51]. What is currently being investigated is at a higher level than COMSEC and the relevance for railways needs to be investigated as well.
Conclusion for 802.11p
The picture given just above highlights the fact that no COMSEC are natively included in 802.11p. Additionally the 802.11p links are only a part of the complete IP Comm System which must be secure from end to end. Using WPA2 appears a good practice in order to restrict the possible devices able to use the APs of the railway IP Com system to access the wayside IP network. It is therefore a first level of protection, even if It is currently not standardized for 802.11p or G5 in the 5,9 GHz band. But WPA2 can't be sufficient as it is not protecting the network connections in particular on wayside between the APs along the track and the secure gateway. Nothing else is provided by 802.11 standard, including the 802.11p, therefore the architecture of the complete IP Comm system for railways must add an additional level of security. IPsec tunnels are required between secure gateways respectively Euro-radio layer in mainline context. Management of the cryptographic material (generation, distribution, update, etc.) has to be done on a secured way, and the hardware should also store that material securely. Key management and more generally cyber security will be a complete subject to be taken into account in future European project in the railway domain.
Communication Security features Conclusion for 802.11p
Identification/Authentication Not addressed
Securisation of the control plane Not addressed GA 730640 Page 112 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Integrity of messages Not addressed Confidentiality of messages Excluded (no WPA2 in G5). To be addressed at INFOSEC level
Availability of the communication To be addressed at the architecture level
Table 6.20 – Conclusion for 802.11p
6.4.6. Existing Communication security features in SATCOM
6.4.6.1. Security overview Satellite communications (SATCOM) play a key role in the telecommunications environment. Since the last years the SATCOM civil applications are much extended. This fact makes these technologies more exposed and have been demonstrated different vulnerabilities. The main threats for SATCOM systems are the following:
· Jamming & blocking have the goal of locking the transmitted information by means of intentional blocking or jam of the source signal using radio frequency transmitter devices. This kind of situation could provoke an availability problem (Denial of Services) in the use of the SATCOM based systems, in the absence of appropriate mitigation techniques.
It is important to distinguish two different kinds of SATCOM jamming:
o Orbital jamming that sends malicious signals directly towards a satellite through an hacked uplink station or by means of its own generator that require high power and precise targeting system; o Terrestrial jamming that occurs in a specific location and involves single terrestrial equipment instead of targeting the in orbit satellite itself. Terrestrial jamming sends malicious signals directly towards the satellite antenna at the end user level. These malicious frequencies can interfere only with satellite signals in a very restricted area (typically 5 km). · Spoofing attacks could compromise the security and even the safety if they are not well detected, of the SATCOM based system. For this reason they are to be taken into greater consideration than jamming attacks. · Cyber attacks in the sense of the same cyber threats encountered in the terrestrial IP based infrastructures.
There are other critical aspects that can affect the SATCOM as the non-intentional interferences, e.g., atmospheric effects (scintillation), sun alignment parasitic effects, exceptional solar storms. GA 730640 Page 113 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
These vulnerabilities could affect the availability of the transmission so need to be balanced by technical means such as diversity of transmission.
6.4.6.2. Security mechanism and related initiatives in progress Concerning jamming & blocking threats, some specific technologies developments are in progress, aiming to provide satellites with on-board interference mitigation capabilities that will allow to tackle interference that could reach them. Moreover, ground-based capabilities, like digital signal-processing modems will take this interference out of the downlink signal. In removing this interference, the jamming can’t be passed on further. One of these development initiatives is the Protected Tactical Waveform (PTW) leaded by Intelsat, that is one way to counter these emerging jamming efforts, providing to U.S. military air forces the capabilities to operate on battlefields where cyber and electronic warfare tools are part of the enemy’s arsenal. PTW include built in interference mitigation capabilities and will be optionally used over steerable spot-beams, as already operational with military SATCOM, providing protected communications over both government and commercial satellites. Combined with new upcoming Intelsat High-Throughput Satellite (HTS) platform, PTW will deliver broader protection, more resiliency, more throughput and more efficient utilization of satellite bandwidth. In December 2013, the European Defence Agency (EDA) launched the initiative related to the preparation of the next generation of Governmental Satellite Communications (GovSatcom) through close cooperation between the Member States, the European Commission (by DG GROW) and the European Space Agency (ESA). Fostering civil-military synergies so that a common solution can address governmental SATCOM demands for security and defence. EDA identified user needs and requirements, assessing the suitability of various solutions to fulfil these requirements for military purposes. In parallel, the European Commission is currently performing a similar exercise for the civil sector. ESA is supporting both initiatives with its background and expertise in satellite communications to develop the candidate architectures and technology developments. OHB Company has proposed innovative solutions for GovSatcom, More in general, to avoid all the others mentioned possible vulnerabilities, different countermeasures are implemented in SATCOM applications. Some of the measures are implemented in the software receivers or at higher application level, guaranteeing both the signals integrity and also the communication confidentiality. The main approach is based on the capacity to discriminate the corrupted or modified data and to protect from external attacks using state of the art security measures. The National Institute of Standards and Technology (http://www.nist.gov) cyber security policy follows the approach: (1) identify; (2) protect; (3) detect; (4) respond; and (5) recover, which can be applied to the SATCOM domain. This could still
GA 730640 Page 114 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models imply an availability problem but does not compromise the safety. Some specific countermeasures are listed here:
· Monitoring the signal strength: · Absolute signal · Relative signal strength · Signal of each received satellite signal
· Monitor satellite identification codes and number of satellite signals · Time protections: · Check time intervals · Time comparisons
· Cyber-attack protections: related with the IP vulnerabilities we can find the following kinds of problems: · Backdoors · Hardcoded credentials · Insecure Protocols · Undocumented Protocols · Weak Password Reset It is also possible to integrate cryptographic data authentications so the received data is further protected. This implies establishing mutual authentication processes between the emitter and the receiver avoiding the interferences of external sources.
6.4.6.3. Conclusion There are real security threats that could affect SATCOM. There are a lot of similarities to the cyber-attacks experimented in the end-to-end IP based networks. It is necessary to learn from other domains experiences and if basic security rules, procedures and guidelines are taken into account, the cyber threats in SATCOM can be mitigated. The integration of the SATCOM based solutions inside the railway applications are part of more complex systems which are designed to prevent the safety related issues under the safety levels. Diverse based systems, multi-frequency receivers and ruggedized waveforms should imply a much higher level of security.
Communication Security features Conclusion for SATCOM Identification/Authentication Available (not standard)
GA 730640 Page 115 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Communication Security features Conclusion for SATCOM Securisation of the control plane Not addressed
Integrity of messages Available (not standard)
Confidentiality of messages Available (not standard)
Reliability of the communication Jamming, blocking and spoofing could be weaknesses of SATCOM when mitigation techniques are not adopted
Redundant transmission means To be addressed at the architecture level of the IP Comm system
Table 6.21 – Conclusion for SATCOM
6.4.7. Impact for IP COMM SYSTEM
6.4.7.1. Transmission security features in each technology Aggressive jamming is a severe threat for a Satcom transponder as for an atmospheric Base Station (LTE or G5). In both cases current waveforms with high bit density are not protected against jammers as they used to be with Frequency Hopping (FH) and Direct Sequence Spread Spectrum (DSSS) in the past. Notice that FH-OFDM has been tested by the military but is quite complex to implement. However, it is a candidate waveform for 5G cellular networks. An atmospheric jammer for LTE is a simple and compact device, which can impact one or few Base Stations, not a complete network. A GEO transponder jammer needs a high power amplifier and a large antenna4, and can be dangerous, because it can block a whole beam covering an European country, therefore a big number of users, An atmospheric jammer can be quickly located and neutralized. A GEO jammer is impossible to be located without airborne sensors scanning the footprint. Jamming a ground Satcom receiver is more likely feasible and it can occur in a specific location, involving single terrestrial equipment instead of targeting the in orbit satellite itself.
4 Only jamming with 1 kW magnetron tubes and standard antennas; saturating with >10 kW magnetron tubes and high gain antennas which are easy to point at GEO satellites. GA 730640 Page 116 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Beyond purely saturating devices, sophisticated jammers could be considered, but they are not always consistent. War is continuing between the arrow and the shield, but at every step the arrow is innovative and can win. As an example, reactive jammers have been developed to countermeasure Satcom spreading waveforms (which are a shield against conventional jammers). Now a new mitigation strategy is considered to fight against them, using an adequate coding and interleaving scheme. For a sophisticated attack, it is well known than synchro patterns are vulnerable, especially in TDMA format (a synchro break leads to a short-term network crash). That is the reason why the military uses to remove synchro patterns from communication frame formats when every user is synchronized (e.g. with some STANAG standards about Tactical Data Links). But civilian GSM was in TDMA format and has never been attacked through this feature. An attack of LTE via synchro patterns could be anticipated in 5 to 10 years, as reported by USA experts for the future FirstNet (last resort federal network, which shall be secured against any threat). But last releases of LTE go into more flexibility for the synchronization, noticeably to cope with outages of GPS or GNSS (which are mostly used as pilots). Noticeably, a LTE subnetwork will be able to survive without master synchronization. In ITS domain, projects about vehicular LTE involve small cells with self-synchronizing (no external pilot). Notice that Automatic Identification Service in S-TDMA is already able to do so for maritime traffic on a large scale.
Transmission Security LTE 802.11p (G5) SATCOM features
Reliability of the Jamming is still Jamming is still Jamming is still communication possible, at one or possible, at one or possible, for one few cells scale. few AP scale beam (a country) or As countermeasures: As countermeasures: a global footprint. - jammer is easily Intelsat will offer - jammer is easily located & PTW for its next located & neutralized neutralized HTS satellites
Table 6.22 – TRANSEC features of each vector compared to requirements
6.4.7.2. Summary of Communication Security features in each technology The following table summarizes the situation of each studied technologies regarding the requirements for the complete IP Comm System: GA 730640 Page 117 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Communication Security LTE 802.11p (G5) SATCOM features
Identification/Authentication Native Not provided by Not provided by of senders the technology. the technology. IPSec to be added IPSec to be added
Securisation of the control Yes No protection No protection plane
Integrity of messages User plane level not Not provided by Not provided by protected. IPSec to the technology. the technology. be added IPSec to be added IPSec to be added
Confidentiality of messages To be added at user Through WPA2 if To be added at user plane level allowed for CBTC plane level (not implemented in ITS)
Redundant transmission To be addressed at the architecture level of the IP com system means
Limited latency and jitter Good Depends on the Sufficient performances, to load of the channel performances for be further regional mainline investigated at high speed
Table 6.23 – COMSEC features of each vector compared to requirements
It clearly shows that the security manager needs to add security features at the application level in addition to what is provided by the transmission technology itself.
6.4.7.3. Limitations of the countermeasures against Deny of Service
SWOC implementation shall provide a means to counteract unintentional interferences and intentional jamming/blocking. The countermeasure mechanism can be derived from the analysis and test performed during the European SECRET project.
GA 730640 Page 118 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
The European project SECRET for “SECURITY AGAINST ELECTROMAGNETIC ATTACKS” has addressed the issue of electro-magnetic attacks against rail infrastructure. The ElectroMagnetic (EM) attacks that have been considered are low power intentional interferences that can break the voice and signalling communication links.
The SECRET Project has been based on the following approach:
· Threat analysis and risk assessment of EM attack scenarios The project has illustrated the risk by implementing some electromagnetic attacks and analysing their impacts.
· Definition of sensor and method to detect jammer that can be located on board or along the track. · Definition of static and dynamic countermeasure against intentional interferences · Recommendation for a resilient railway infrastructure to EM attacks
Several Jammer detection techniques have been studied, analysed, implemented, tested and compared:
· Detection based on the Error Vector Magnitude (EVM) monitoring · Detection based on the spectrum frequency occupation monitoring · Detection of an excess of energy in the operation band · Detection based on the QoS monitoring
The study has shown that all these detection techniques are complementary because some of them are narrow band and very sensitive and other are wide band but less sensitive. It is the combination of a narrow band jammer detection and of a wide band detection that will increase the resilience of the system to intentional interference.
In order to use in an optimal way the different interference sensors to implement the different countermeasure strategy, an adequate communication Resilient Communication Architecture (RCA) has been proposed.
This RCA is composed of the following main modules:
· Track detection system · On-board detection system · Track Health/Attack Manager · On-board Health/Attack manager GA 730640 Page 119 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· Central Health/Attack Manager · Multi technology communication system
The RCA will impose that the Telecom system specified in ERTMS becomes technology independent to allow the use of different types of technology such as GPRS, LTE, WIFI, and Satcom. Several recommendations have been issued by the SECRET project. These recommendations can be divided in the following three categories:
· Prevention from EM jamming effects concerns the recommendations that can be adopted permanently such as: integrating communication via different technologies. · EM attack detection: It concerns the different detection technics with their potential applications. · Mitigation of EM jamming effect: The recommendations of this category concern the definition of actions that can be launched during a short period to limit the impact of an EM jammer such as: o Increase temporarily the output power of a BS or Train mobile output power o Switching from train front cab radio to the rear cab radio if possible. 6.5. Network providers
The implementation of the wireless link may be done either autonomously by the supplier and the link becomes a private asset of the Infrastructure Manager. Or a technology of a public (local or a global) network provider of various networks types (IoT, cellular) may be hired to provide the wireless link.
6.5.1. Public
There are many public providers, like mobile operators, WI-FI providers, IoT network providers, fibre optic network providers and so on. Each of them usually continuously improves characteristics of their networks – their services. So, it is possible use their services. But in this case the availability of the service dependent upon the QoS of their network. First, this creates a demand for reliable external supplier and a high level of data security and, second, it creates a dependence on the stability and economic profitability of the service and its provider.
GA 730640 Page 120 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 6.5.2. Private
Private network, owned by the Infrastructure Manager, has the same requirement on the level of data security but such a level can be achieved with a bit lower cost, especially the cost of administration. The protection levels generally need to be the same. This type of network markedly increases maintenance requirements. Expansion and improvement of the networks will not be as fast as of the commercial networks. But the OPEX of the service may be lower if designed and implemented in an optimal way. And the operating stability is only constrained by the stability of the owner himself.
6.6. Spectrum management
Radio frequency spectrum is divided to two main domains. The first are free frequencies and the second are licensed frequencies. Frequencies are divided by national telecommunication institute. For example: Czech spectrum table: http://spektrum.ctu.cz/en/band European Radio communications Committee (ERC) within the European Conference of Postal and Telecommunications Administrations (CEPT) manages radio spectrum use in Europe.
6.6.1. Free frequency bands
License-free frequencies, like ISM bands, are available for each user. Many devices can share the band freely without any regulation either on a professional and industry application level or privately at home or outside a building - outdoor. Typical outdoor use are mobile terminals - in cars, in trains or in a pocket.. Only emit powers are limited by international or national regulations. Nevertheless high levels of interferences in these frequency bands can arise both systematically and randomly in time. The only effective defences against interference are use of suitable advanced modulation techniques which usually employ frequency hopping or spread spectrum modulation with low-density power per Hz, carrier sense multiple access / collision avoidance techniques. Besides that using short transmission periods (bursting) help to avoid spectrum congestion. Below table summarizes spectrum ranges used in countries worldwide for the most used ISM band:
GA 730640 Page 121 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
ISM band allocations in the world
Country Band limits (MHz)
China 755 - 787
Europe 863 - 868
Japan 916.5 - 927.5
Korea 917.5 - 923.5
Singapore 866 - 869 &
920 - 925
USA 902 - 928
Table 6.24 – ISM band spectrum allocations
Devices using license-free bands have to undergo homologation process. Only specific amateur radio transmitters need not be homologated. Typical technologies used in license-free bands are:
· Bluetooth (IEEE 802.15.1) · IEEE 802.11 family (WiFi, G5,..) · IEEE 802.15.4 family (ZigBee, 6LoWPAN,..) · LoRaWAN
6.6.2. Licensed frequency bands
Using licensed frequencies must be confirmed by a national office. This requires more administrative activities versus free bands. In this case nobody else can use the licensed frequencies in a specified area. Hence very low levels of interference results with such application. A systematically use of devices for licensed band would usually require to apply for a service from an operator, like GSM operator or IoT communications operator. Typical technologies for licensed bands are:
· GSM · UMTS GA 730640 Page 122 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· LTE
6.7. Technical requirements and characteristics
6.7.1. Data bandwidth/throughput and timing latency
The following table list typical requirements for useful data, i.e. basic payload for control or status indication messages of various field elements.
Type of Field Data per message (control or Communication Comment Element status/acknowledgement) cycle typ./ max. [bits] possible latency [ms]
Audio frequency 2 200/500 Only occupancy track circuit detection (no coding data) + self-diagnostic
Relay track circuit 2 200/500 Only occupancy detection (no coding data) + self-diagnostic
LED signal 2 200/500
Incandescent 1 200/500 signal lamp
Halogen signal 1 200/500
LED speed 4 200/500 indicator
Gate Barrage 1 200/500 Indicator
Point machine, 3 200/500 24/144 VDC
GA 730640 Page 123 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Type of Field Data per message (control or Communication Comment Element status/acknowledgement) cycle typ./ max. [bits] possible latency [ms]
Point machine, 3 200/500 220 VAC, 3 x 400 VAC
Heating for 1 1 000/20 000 switches/points
Digital 1 200/500 input/output 1 bit
Axle counter 2 200/500
Relay 1 200/500
Level-crossing 4 200/500 barrier
Level-crossing 6 200/500 warning board
Level-crossing 2 200/500 annulment circuit
Complete Object 64 - 256 200/500 Controller
Table 6.25 – Typical useful data for field elements
These figures might look like that the data throughput and consequently the required bandwidth for communication links is very low – in the range of tens of bits/s. Only if a complete Object Controller should be connected via a wireless link some consideration of the technology’s data throughput should be carried out as it requires a throughput for the payload in the range of kbits/s. We need to talk both about data bandwidth and data throughput. In many cases the wireless technology allows to transmit data at high rate but only for a fraction of the time in order to allow GA 730640 Page 124 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models for sharing available spectrum with other transmitters in the vicinity. High bandwidth enables the messages to be transmitted quickly with low delay. But the overall data throughput depends on the rules of the technology which specify and govern the maximum fraction of the time that is allocated to a single node to transmit and receive messages. We also have to take into account that for a safety application of most of the above listed field elements we need to add necessary protection mechanisms – defences, which require more data carried by the safety message/protocol. The applications have to comply with the requirements of the standard EN 50159, hence adopting overhead data for the protection mechanisms against the hazards listed in paragraph 6.4.3 . So, typically, a message needs several bytes of data to be added into the payload to implement the safety layer of the protocol. Common safety protocols have message (incl. header) lengths of 40 – 64 bits. Compared to this, useful data of the field elements add almost nothing to the payload. Only for non-safety applications, like e.g. heating for switches, much smaller overhead is required. This doesn’t take into account current security requirements. The additional overhead for lower communication layers like network or security layer may range from 32 – 256 bits. Therefore typical application with communication period of 200 ms will need data throughput of between 1 and 2 Kbit/s. Hence the overall required bandwidth, including the physical and link layers, will be almost in the same range since it adds only about 10 – 30 % to this figure. Such a bandwidth may seem to be not high but it obviously eliminates some IoT technologies or protocols. Most other wireless technologies are capable to provide such a bandwidth. On the other hand, latency of the transmitted data is critical for most field elements. It brings another challenge to the candidate technologies. Since the typical required latency is 200 ms this translates to the maximum latency of roughly 100 ms for physical layer as any basic processing of protocols inside the communication transceivers and associated networking devices add considerable delay in presenting the transmitted data to the application. If we take into account also the fact that many technologies need to resolve conflicts in the band using repetitive sending of frames using CSMA techniques and/or using “listen before transmit” way of access to the allocated spectrum, the length of transmission of each frame has to be at least twice as shorter. Therefore the necessary bandwidth for safety critical data communications is mostly above 5 kbits/s. Only for non-safety applications the bandwidth may be even 100 x lower. Hence the basic requirements on the wireless technology for safety applications are:
GA 730640 Page 125 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· data bandwidth > 5 kbit/s · data throughput > 1 kbit/s · latency < 100/400 ms (depending on the application)
For non-demanding, especially non-safety applications:
· data bandwidth > 1 kbit/s · data throughput > 40 bit/s · latency < 20 s
Higher bandwidth technologies might be useful and applicable but they will usually bring some disadvantages like higher cost, lower distance range, higher power consumption etc. Upper limit for suitable bandwidth of the candidate technology can be approximated as 100 Mbit/s though it will never be fully utilized. The limit is only a practical measure in order to allow for low-latency technologies to be considered while avoiding very high data rate services. So, selection based on these criteria needs to be done resulting in compromise from the point of view of the real application. Some may need lower range and need not be limited by the power supply, some may need higher range and lower power.
6.7.2. Distance ranges
Most long-range connections of field elements to the central device like Object controller or IXL do not cross distance range of 10 km. Majority of connections for such applications are in the range of 100 – 3000 m. Even lower connection distances around 30 m are used for applications like Level-crossing warning board to controller or Level-crossing annulment circuit. If radio connection for applications with less demanding requirement on latency would be used for interconnection it might be interesting for users to cover even higher ranges than 10 km. Satellite technology could serve this easily but proper economic viability analysis would be necessary. So, it can be summarized that the ranges required in obstacle-free environment (which translates to about a half reach with obstacles in the connection direction) of the suitable wireless technologies shall be:
· distance range > 100 m up to > 10 km
6.7.3. Power consumption
The range of power consumption of the wireless transceivers is very high, starting from several mW for IoT technologies to tens of W for high bandwidth devices.
GA 730640 Page 126 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Based on the assumptions coming from the previous paragraph, technologies providing sufficiently high bandwidth and low latency will rarely be able to work on power supplies delivering less then few watts. Mostly the need for power will start at about 5 – 10 W.
6.7.4. Transmission dependability
Technically ideal solution for applying wireless transmission is the use of the licensed band. This would bring the best controlled spectrum allocation and low interference. But it adds considerable cost from the point of view of deployment and operation. It also adds time to the installation and commissioning. Using license-free band brings advantages in price for the client and much easier deployment process. But the technology selected will need to be immune to possible interference from surrounding sources. The fact is that for railway lines in the outskirts of the big cities the sources of interference are scarce. It is also necessary to take into account the possible sources of interference on-board of trains on the line. So the application needs to take into account the usual installation sites for it and the train technology which tends to employ more and more wireless transmitters on-board.
6.7.5. Line security
Current security technologies are capable to adequately protect the radio links for most of the listed wireless technologies. But the deployment plan has to include also a plan for implementation of the suitable security protocol stack and, along with it, also the plan for key/certificate management and respective future upgrade.
6.8. Maintenance
Compared to wire connections wireless terminals usually need higher level of maintenance. But the requirements on maintenance are fully comparable to those of Object controller and “intelligent” field elements. It can be expected that most field elements using radio connection will have its own CPU with memory because it will communicate with its partner via a data protocol. Some applications might use simple field elements with only a relay or 1 bit signal interface. But this would limit both functional and diagnostic capability of the end device which would result in limited performance and increased demand on maintenance. Hence it can be expected that, in the end, integrated device will be implemented as Smart Wayside Object Controller. Both parts of such device – functional and wireless terminal – will need a comparable level of operational diagnostics and maintenance.
GA 730640 Page 127 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Practically the only major difference between those two parts is the antenna. But nowadays antennas are designed often as plastic boxed device requiring zero care. So, normal maintenance procedures for outdoor electronics have to be applied for wireless parts of those smart devices. Built-in intelligence brings the advantage of better diagnostics and ensures conditions for predictive or condition-based maintenance. But, there is another challenge for the maintenance of SWOCs. The wireless links may, from time to time, gradually or suddenly, suffer from increased level of interference from surrounding radio devices which are usually out of control of the user of the link to the specific SWOC. The interference may, without any advance notice, rise remarkably thus negatively influencing the performance of the link. Besides that a change in the environment, a new obstacle in the direction of the link may occur; which is critical if the link requires direct LOS. Even a new building may appear in the vicinity of the SWOC or of the link. The only prevention is: a. on-line autonomous check of the SNR (signal-to-noise ratio) by the transceivers and automatic issuing of the alarm in the diagnostic layer when some predefined limit is achieved, b. periodic check of interference in the used spectrum band on at the concrete allocated frequency by the maintenance personnel, c. Periodic check of the environment for changes or emerging obstacles by the maintenance personnel.
Besides that, in case when using services of public network providers, the user of the link may, from time to time, face the request or even a not notified change of the network configuration or availability issue which calls for immediate start of consultations or negotiations with the provider. The risk of such situation is highly depending on the QoS arrangements in the SLA (Service-level Agreement) and, of course the dependability of the provider. The personnel has to be trained how to solve such situations.
6.9. Result of the Analysis
Based on the requirements specified in previous paragraphs suitable candidate wireless technologies can be identified. The fact is that the selection is not a simple task if several criteria have to be applied at once:
· data throughput · distance range GA 730640 Page 128 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· timing latency · power consumption
The ranges and data throughput required by SWOC applications are not difficult to fulfil. But timing latency adds a highly critical aspect of the selection process. Power supply of field elements is also of important concern but the fact is that most field elements consume a considerable amount of power and therefore the added demand for power from the wireless terminal is not prevailing. The cost of the link needs to be evaluated based on the detailed specification. Especially cellular networks provide numbers of different profiles resulting in highly variable pricing. Generally, it can be expected that only packet-switched profiles can be taken into account since circuit switched would cost too much if used as permanent connection and, on the other hand, could not provide low latency if used periodically or on demand The cost of the service is also dependant on the connection mode. Circuit-switched services generally tend to cost too much as the connection has to be maintained all the time. It is hardly possible to set up the circuit every 500 ms. So, generally, only public packet services can be used for the purpose. In the end, candidate wireless technologies need to be categorised according to the application. The demanding safety critical applications will require low latency (or real-time response) and permanent packet exchange. Some of them may not require permanent exchange but event driven time-to-time data exchange. But some applications, predominantly non-safety critical, are immune against high latency and do not require frequent data exchange. Below table lists candidate technologies which fulfil most of the requirements:
CANDIDATE WIRELESS TECHNOLOGIES
Applicable to safety critical real-time response applications
Nr. Type Bandwidth Range Latency [bit/s] [m] [ms]
A1 IEEE 802.11 a/b/g/n/ac (WiFi) 11 M – 1000 M 50 – 250 1 - 10
A2 IEEE 802.11ah (HayLow) 65 k – 234 M 100 – 1000 ?
A3 IEEE 802.11p (ETSI ITS-G5) 6 M – 108 M 50 - 300 40 – 200
GA 730640 Page 129 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
CANDIDATE WIRELESS TECHNOLOGIES
Applicable to safety critical real-time response applications
Nr. Type Bandwidth Range Latency [bit/s] [m] [ms]
A4 IEEE 802.15.4 ZigBee 20 k – 250 k 100 – 1000 10
A5 IEEE 802.15.4 Thread 250 k 10 – 100 100
A6 WiMAX (IEEE 802.16) 6 – 376 M 1000 – 50 k 50
A7 EnOcean (ISO/IEC 14543-3-10) 125 k 10 – 300 30
A8 UMTS (selected packet-switched 2 M > 50 k 200 – 700 profiles)
A9 HSPA (selected profiles, e.g. 2 – 168 M > 50 k 30 - 200 EDGE...)
A10 LTE (selected profiles) > 100 M > 50 k 20
A11 Symphony Link 10 – 250 k < 50 k > 100
Applicable only to non-safety critical high-latency immune applications:
B1 ITU 9959 Z-Wave 9.6 – 100 k 20 – 150 200
B2 LoRaWAN 0.3 – 50 k < 20 k > 4000
B3 NB-IoT 250 k > 50 k > 1600
B4 UNB/Sigfox 0.1 – 1 k < 50 k > 4000
B5 SATCOM IRIDIUM (LEO) 250 k – 8 M global 1800
B6 SATCOM INMARSAT BGAN (GEO) 10 k – 492 k global 800
Table 6.26 – Candidate wireless technologies
GA 730640 Page 130 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
The figure below shows the graph of range versus data rate (bandwidth) X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
7. Analysis of the state-of-the-art of power supply
7.1. Purpose and Scope
The scope of this chapter is to form a basis for exploring technical possibilities within the power supply area in order to supply local energy for a Smart Wayside Object Controller. (Related to this, it is also relevant to investigate how to decrease the power consumption in the object controller as well as in the field element itself.) The following areas are studied,
· Ambient power Electrical power from catenary, solar energy, wind energy etc. · Energy storage Batteries and capacitors. · Power consumption Requirements from object controller field elements Possibilities to reduce the power consumption · Maintenance aspects Load/charge cycles for the energy storage Fault and Quality Supervision · Others Form factor Environment requirements
The study about ambient power and power harvesting is on a general level as a deeper study is a task for an open call related to X2Rail-1.
7.2. Objectives
The purpose of this chapter is to investigate possibilities to make the object controller, and field elements, “self-sufficient” in energy. With self-sufficient means, that energy is produced locally and not distributed from a central power plant. The aim is to reduce or avoid the needs for power cabling. X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 7.3. Power Consumption
7.3.1. General
The ’law of conservation of energy’ states that the total energy of an isolated system remains constant. That is, in order to understand how much energy that needs to be supplied from energy harvesting and also needs to be temporary stored, the power consumption of the controller have to be estimated. In other words, input (of power) must at least be bigger than output. An initial hypothesis is that the energy required will have impact on the form factor of the Smart Wayside Object Controller as well as the architecture. For example, in cases with low energy demands it can be assumed that power components (batteries, solar cells etc.) can be kept small in size. This would make it possible to integrate the SWOC with the field elements themselves (Figure7.1).
Figure 7.1 – Object Controller and power source integrated in the field element
Used symbols are explained in Figure 7.2 – Symbols used in figures – Symbols used in figures
GA 730640 Page 133 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Figure 7.2 – Symbols used in figures
On the other hand, high-energy demands will probably require bigger components, resulting in a local but centralized energy supply for one SWOC or several SWOCs controlling a group of field elements. - Object Controller managing a group of field elements, one power source for the site).
GA 730640 Page 134 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Figure 7.3 – Object Controller managing a group of field elements, one power source for the site
A middle way could be to use a common power source for high-energy users and integrated wireless object controllers for the rest of the field elements (Figure 7.4 – – Common power source for high energy users).
Figure 7.4 – Common power source for high energy users GA 730640 Page 135 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Below is a rough estimation of the power consumption for the Smart Wayside Object Controller as well as for the field elements. Sample figures have been taken from “typical” and existing products.
7.3.2. Object Controller
Power consumption for an existing object controller is in the range of 10 - 20 Watts. Future object controllers should not exceed this. Adding wireless communication may increase the power consumption. A “typical” small radio transceiver circuit with a range of 1-2 km uses 50 mW when active and 10 mW when idle, but an increase of a couple of Watts may be possible depending on the chosen technology. A complete external radio (radio, interfaces, display, cooling …) consume more power, below are a few examples,
Type of Radio Power Consumption Comments
GSM 6W
TETRA 130W
UHF 30 W
Siemens Simatic Scalance <12W 2G, 3G technology radio module
WLAN short range router 10W
Satellite antenna 12W
Table 7.1 – Consumption of external radio
7.3.3. Field Elements
The table below is based on data from several different field elements gives an indication of the power consumption. As there can be a significant variation in consumption depending on customer requirements and manufacturer the table show typical values given in data sheets from equipment manufacturers. GA 730640 Page 136 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Type of Field Element Power Consumption Comments
Audio Frequency track ~ 100 W circuit
Relay track circuit 25 – 200 W Depending on length of the section, 0-1000 m
LED Signal ~ 5-20 W per LED lamp
Incandescent lamp 20-30 W when lit Typically used in ADIF signals
Halogen Signal <50 W when lit
Point machine, DC 24/144 V ~ 1400 – 1600 J per This corresponds to the operation energy consumed by one Example: 24 V, 20 A during 3 LED signal lamp during about s 2.5 minutes or an AF track ð 24*20*3 = 1440 J circuit during 15 seconds.
Point machine, 220 VAC < 2 kVA during 4s (<8000 J) 5 W when not moving
Heating for switches/points 5-23 kW Used between +4 - -25 degrees Celsius to melt ice and snow.
Digital input/output < 1W when conducting
Axle counter ~5W per counting head
Relay <10 W
Table 7.2 – Consumption of field elements
GA 730640 Page 137 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 7.3.4. Reduction of Power Consumption
The trend is that the power consumption in technical equipment and systems is gradually reduced for each new generation due to e.g. newer low power components, more efficient SW algorithms etc. It is therefore expected a reduction of the power consumption per device in the future. For example, for the fifth generation mobile system (5G) there are two objectives related to energy saving, “90% reduction in network energy usage” and “Up to ten year battery life for low power, machine-type devices” From reference [3]. For railway lines with lower traffic intensity it may be possible to save energy by entering low- power mode at times when there is no traffic, only powering the minimum necessary components. Full power is then switched on when a train is approaching. Using radio signalling and moving block should reduce the number of field elements, thus reducing power consumption.
7.4. Energy Harvesting
7.4.1. General
To fulfill the vision about ‘self-sufficient smart equipment’ energy should be produced and stored locally in an amount to meet the need from the Smart Wayside Object Controllers and from connected field elements. There are two extreme cases, - In the case when power is only intended for the object controller itself (object controller = microcontroller + radio), then harvesting and energy storage equipment should be possible to be small in size and maybe be integrated in the object controller. For example a combination of a solar cell/piezo-electric generator and a battery/capacitor. - In the case the power source is intended also to feed other equipment, e.g. the field elements, the harvesting and storage equipment will probably require a large space. In this case it should be considered that several object controllers and field elements (a whole site) share the power supply.
In order to guarantee uninterrupted power supply, redundant power needs to be considered. The power-sources should be compatible but not the same, e.g. solar-wind instead of solar-solar or wind-wind. To produce energy one can imagine taking power from catenary, re-generating energy from trains (brakes, vibrations), solar energy, wind energy etc. For the time being this task will be studied in
GA 730640 Page 138 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models an open call about Energy Harvesting, S2R-OC-IP2-02-2017, that will start in autumn 2017. See also http://ec.europa.eu/research/participants/portal/desktop/en/opportunities/h2020/topics/s2r- oc-ip2-02-2017.html Chapter 7.4.1 to 7.4.6 shows a few possibilities to be studied but the list should not be considered exhaustive.
7.4.2. Catenary
In case the railway is electrified, it is possible to use energy from the catenary or from electrical grid.
7.4.3. Solar Energy
Solar energy may be used depending on location, i.e. if there is enough light at the location in question. A challenge is also to find a low power technology and good energy storage. A typical solar panel today may produce around 200 Watts peak power per square meter. However, the actual output power is dependent on a number of parameters like geographical location, weather, environment temperature etc. Therefore, the expected produced energy from an installation need to be calculated from case to case. Design life time is about 25 years. The temperature range for a solar cell is quite wide, but the output power changes with temperature (depending on the material used for the cell).
7.4.4. Wind Energy Wind power is another possibility, but usually requires quite large facilities. Unreliable wind also requires good energy storage for equalizing. Rated power for small wind power turbines are typically available between 300 Watts to 60 kWatts, with a total height between a few meters up to 60 meters. The start-up wind speed is from 1.5 m/s and rated wind speed (i.e. wind speed required to give peak power) from about 10 m/s. Design life time is about 20 years. Temperature range from -20 to +50 Celsius.
7.4.5. Fuel Cell
Fuel cells are upcoming and an option for the future. Have problems with outdoor conditions and the lifetime is not really proven. It could be considered as power backup. Example: Direct Methanol Fuel Cell (DMFC) A typical commercial DMFC reach a power of about 200W, but there are some that produce up
GA 730640 Page 139 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models to 5 kW. Dimensions for a 200 W cell are around 40 liters (like standard cabin luggage). Typical combustible consumption is about 0.8-0.9 l/kWh. Temperature range from -20 to +50 Celcius.
7.4.6. Re-generating Energy
Energy re-generated from the railway system, e.g. energy during braking that is re-injected from the train into the electricity network, or piezo-electric devices that uses vibrations from the rail to generate power.
7.4.7. Availability of Energy Sources and System Design
To guarantee uninterrupted power supply, either in case of 100% locally harvested power, or when using an untrusted power grid, the availability of each source need to be carefully examined and in probably most cases a redundant power source should be considered. When using a battery as energy storage it is possible to for a short while, depending on the size of the battery (in Ah) and the energy demand, manage without energy input. This is called ‘autonomy’ time, and may last from a few minutes up to several days. However, the cost of a large battery at a high load level and the risk to lose the field element from an empty battery will probably mean that there is a need for an alternative energy source. How much electrical energy that is possible to produce from solar and wind depends on geographical characteristics, especially the solar irradiation, temperature levels and average wind speed at the specific site. These characteristics usually vary over the year, and when designing the power system the characteristics need to be known for the site. For example, at high north latitudes the light is much more available in the summer season than in the winter. Local data over solar radiation, temperature and wind are managed by meteorological institutes and are usually integrated in professional tools for energy system design. See also global maps of solar irradiation and wind speed below. To summarize, using for example only solar or wind energy to charge energy storage may be enough in good conditions. Depending on the location of a site, the “good conditions” may occur during a large part of the year, while during a number of months (or days, with clouds or not enough wind) an alternative power source is necessary. A large battery can handle a long time with low energy input, but may be expensive. To back-up the renewable energy sources, fuel cells or combustion engine (diesel) generators may be needed.
GA 730640 Page 140 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Figure 7.5 Global Solar Irradiation Europe
Figure 7.6 Global Map of Available Wind Energy Europe
GA 730640 Page 141 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
In additions to vendor specific characteristics, such as lifetime due to e.g. used components and design consideration, the key characteristics related to availability per energy type are, - Solar Energy Location, which determine the available light over time. Weather, e.g. amount of clouds and snow which reduce or cut off the light. Temperature, high temperature will reduce the produced power. - Wind Energy Location, which determine the average wind speed. There is also a minimum wind speed for power production. - Fuel cells and combustion engine generators Fuel consumption, which depends on the size (in kW) of the generator/cell and the load. In general, a fuel cell is more (double) efficient than a combustion engine. Depending on type, a fuel cell may take up to 30 minutes to start-up.
Beside the energy sources and the energy storage (battery), a key component in a power system is the operational control function, which have three basic tasks, - To keep the system operational in order to supply the load with power - To minimise fuel and maintenance costs E.g. a typical diesel engine normally reach maximum efficiency at 100% of its nominal power, at 50% of nominal power the efficiency is 20% less and it drops steeply. - To optimize the life of the battery and generator E.g. there are limits to the amount of storable energy and load of a battery and the aging of a battery is highly dependent on the employed charging technique.
The design a power system includes a number of questions in the following areas that need to be handled (iterative process), - Application of the system Standalone system or backup to electrical grid? - Geographic characteristics in which country/area will the system be installed? What are the solar irradiation and temperature levels? - Power sources which power sources can be used? Solar, diesel, wind etc. - Renewable fraction E.g. ratio between solar energy and diesel energy?
GA 730640 Page 142 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
- Power consumption how much power is consumed per day and per year? AC or DC? Single- or Three-phase? - Power demand What is the peak power demand in a day? - Battery size Autonomy time? Typically between 0,5 and 4 days.
Based on the answers to these questions it is possible to do an initial design for a system.
7.5. Energy storage
7.5.1. General
To store electrical energy there exists a number of possibilities, but most convenient here seems so be to use rechargeable batteries or capacitors.
7.5.2. Capacitors and Supercapacitors
The capacitor is an electrical component that is easy to charge, tolerates high electrical current, withstand many recharge cycles and there are essentially no maintenance needs. There are many applications using capacitors as energy source, camera flashes, laser instruments, uninterruptible power supplies, bug zappers and so on. Recently, there have been breakthroughs with so-called supercapacitors, which have very high capacitance (> 2kF). This kind of capacitor offer possibilities in areas like electric cars, regenerative braking in automotive industry and industrial electrical motors, power backup for computer memory etc. Supercapacitors have short charge and discharge times. It is possible to achieve high charge and discharge currents due to their low internal resistance. Batteries usually may take up to several hours to reach a fully charged state, while supercapacitors reach the same charge state in less than two minutes. The specific power of a battery or supercapacitor is a measure used to compare different technologies in terms of maximum power output divided by total mass of the device. Supercapacitors have a specific power 5 to 10 times greater than that of batteries. This property is especially important in applications that require quick bursts of energy from the storage device. GA 730640 Page 143 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Supercapacitors have a virtually unlimited cycle life. This makes supercapacitors very useful in applications where frequent storage and release of energy is required. Supercapacitors come with some disadvantages as well. One disadvantage is a relatively low specific energy. While Li-ion batteries commonly used in cell phones have a specific energy of 100-200 Wh/kg, supercapacitors may only store typically 5 Wh/kg. This means that a supercapacitor that has the same capacity as a regular battery would weigh up to 40 times as much. Another disadvantage is a linear discharge voltage. For example, a battery rated at 2.7V, when at 50% charge would still output a voltage close to 2.7V, while a supercapacitor rated at 2.7V at 50% charge would output exactly half of its maximum charge voltage – 1.35V. This means that the output voltage may fall below the minimal operating voltage of the device running on a supercapacitor. A solution to this problem is using DC-DC converters. However, this approach reduces performance. Cost is the third major disadvantage of currently available supercapacitors. The cost per Wh of a supercapacitor is more than 20 times higher than that of Li-ion batteries. However, cost can be reduced through new technologies and mass production of supercapacitor batteries.
7.5.3. Batteries
7.5.3.1. Conventional Batteries Rechargeable batteries consist of materials that via chemical reactions produce electricity during discharge/use. By applying an electrical current, the reaction is reversed, thus charging the battery. Because of self-discharge, batteries need periodic recharges. The most common rechargeable batteries are lead-acid, NiCd, NiMH and Li-ion.
· Lead Acid Lead acid is rugged, forgiving if abused and is economically priced, but it has a low specific energy and limited cycle count. Lead acid is used for wheelchairs, golf cars, personnel carriers, emergency lighting and uninterruptible power supply (UPS). · Nickel-cadmium NiCd is used where long service life, high discharge current and extreme temperatures are required. NiCd is one of the most rugged and enduring batteries, a chemistry that allows ultra-fast charging with minimal stress. Main applications are power tools, medical devices, aviation and UPS. · Nickel-metal-hydride –
GA 730640 Page 144 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
It serves as a replacement for NiCd as it has only mild toxic metals and provides higher specific energy. NiMH is used for medical instruments, hybrid cars and industrial applications. NiMH is also available in AA and AAA cells for consumer use. · Lithium-ion Li-ion is replacing many applications that were previously served by lead and nickel-based batteries. Due to safety concerns, Li-ion needs a protection circuit. It is more expensive than most other batteries, but has high cycle count and low maintenance costs. NCA in the Tesla S 85 has a specific energy of 250Wh/kg, LMO in the BMW i3 has 120Wh/kg and a similar chemistry in the Nissan Leaf has 80Wh/kg. The BMW i3 and Leaf batteries are made for high durability; Tesla achieves this by over-sizing.
Li-ion Property Lead Acid NiCd NiMH Cobalt Manganese Phosphate
Specific Energy 30-50 45-80 60-120 150-250 100-150 90-120 Wh/kg
Cycle Life5 200-300 1000 300-500 500-1000 500-1000 1000-2000
Internal Very Low Very Low Low Moderate Low Very Low resistance
Charge -20 – 50 0 – 45 0 – 45 Temperature [C]
Discharge -20 – 50 -20 – 65 -20 – 60 Temperature [C]
Maintenance 3-6 Full discharge every 90 days Enhanced Maintenance [Months]
3 The number of discharge-charge cycles the battery can experience before it fails to meet specific performance criteria, usually about 80% of original performance. The measure is defined for specific charge and discharge conditions for example the rate and depth of the cycles. A guide to understand battery specifications can be found in reference [15].
GA 730640 Page 145 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Li-ion Property Lead Acid NiCd NiMH Cobalt Manganese Phosphate
Cost Low Moderate High
Table 7.3 – Characteristics for commonly used rechargeable batteries
7.5.3.2. Future Batteries Driven by big technology companies (smartphones), and car companies making electric vehicles, battery technology development has recently started to take off. But meeting basic requirements for a battery is a challenge. Listed are some of the most promising experimental batteries.
· Lithium-air (Li-air) Lithium-air promises to store far more energy than is possible with current lithium-ion technologies, 13 kWh/kg. There are however a number of issues with this technology. · Lithium-metal (Li-metal) In 2010, a trial lithium-metal with a capacity of 300Wh/kg was installed in an experimental electric vehicle. DBM Energy, the German manufacturer of this battery, claims 2,500 cycles, Long-term safety remains an issue. · Solid-state Lithium Solid-state batteries promise to store twice the energy compared to regular Li-ion, but they are not suitable for applications requiring high current. Targeted applications are load levelling for renewable energy source as well as EVs by cashing in on the short charge times that this battery allows. Research laboratories, including Bosch, predict that the solid-state battery might become commercially available by 2020 and be implemented in cars in 2025. · Lithium-sulphur Lithium-sulphur batteries offer a very high specific energy of 550Wh/kg, about three times which of Li-ion, have good cold temperature discharge characteristics and can be recharged at –60°C. The battery is environmentally friendly. A challenge with lithium- sulphur is the limited cycle life of only 40–50 charges/discharges as sulphur is lost during cycling by shuttling away from the cathode and reacting with the lithium anode. Other problems are poor conductivity, a degradation of the sulphur cathode with time and poor stability at higher temperatures. Since 2007, Stanford engineers have experimented with nanowire. Trials with graphene are also being done with promising results. · Sodium-ion (Na-ion) Sodium-ion represents a possible lower-cost alternative to Li-ion as sodium is
GA 730640 Page 146 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
inexpensive and readily available. Na-ion has the advantage that it can be completely discharged without encountering problems that are common with other battery systems. The specific energy is about 90Wh/kg with a cost per kWh that is similar to the lead acid battery. Further development will be needed to improve the cycle count and solve the large volumetric expansion when the battery is fully charged.
Property Lithium-Air Lithium- Solid-state Lithium- Sodium-Iron metal Lithium Sulfur
Specific 13000 300 300 500 90 Energy (theoretical) Wh/kg
Cycle Life6 50 (in lab) 2500 100 50 50 (prototype)
Target Electrical Electrical Wheeled Solar- Energy Application Vehicles Vehicles, mobility, powered Storage Industry Electrical airplane vehicles
Table 7.4 – Summary future batteries
7.6. Supervision and Maintenance
7.6.1. General
It is assumed that standard fault supervision can be performed, for example loss of (primary and redundant) power, loss of charging current, high/low temperature etc. Examples of supervision useful for predictive maintenance are,
· Number of charge cycles of batteries Traditionally a battery’s life-time is related to the number of cycles · Environment temperature Charging a battery at high temperature reduces life-time
6 See previous footnote. GA 730640 Page 147 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
· Reduced charge current from solar cell Performance is reduced for solar cells when aging · Operating hours Standard maintenance should be performed at regular intervals
Note, these examples should not be considered as exhaustive.
7.6.2. Safety and Hazards
Capacitors and batteries can store charge long even after power has been disconnected from the device. They pose a risk for electrical shock (capacitors) and fire hazards (batteries). Because of this risk, to prevent injury it is necessary to discharge capacitors and isolate battery poles before handling them. High-energy capacitors should be stored with their terminals shorted to prevent charge build-up over time.
7.7. Result of the analysis
The purpose of the analysis of power supply was to examine existing and approaching possibilities to make the object controller, and connected field elements, “self-sufficient” in energy. In order to explore this, the power consumption for existing object controllers and typical field elements has been examined. Further alternatives to produce and store energy has been discussed, however a deeper analysis will be accomplished later in an open call about Energy Harvesting, S2R-OC-IP2-02-2017. A general conclusion about power supply and energy is that there are many existing and coming possibilities to ensure the energy supply to a “self-sufficient Smart Wayside Object Controller”. However, a specific solution for energy will depend on actual consumption, which in turn depends on the configuration of the object controller and the railway operation. For example, configurations with very high energy consuming field elements and frequent operation of switched and crossings etc. may need to be excluded. Reduction of the power consumption will be a part of new generations of technology, e.g. by new components and SW algorithms but also methods to reduce power consumption in the railway signalling system, e.g. by using low power mode at times with no traffic, should be used.
GA 730640 Page 148 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 8. Analysis of the state-of-the-art of maintenance and diagnosis
The scope of this document is to form a basis for exploring technical possibilities within the Maintenance and Diagnosis area in order to supply monitoring and supervision for a Smart Wayside Object Controller. It is about monitoring of the connected wayside object or for the object controller itself. The following areas are covered,
· Level of detail and insight information provided · Interfaces (network, protocol, capacity, etc.) · Inputs from other projects/domains
8.1. Introduction
This document is the study of the state-of-the-art about Maintenance and Diagnostic of systems to detect events including failures. In the last decade, normally, failures were detected only by periodic inspections in order to prevent breakdowns, that It is commonly named as Preventive Maintenance or Scheduled Maintenance (From reference [20]). Other Maintenance and Diagnostic systems that are broadly classified are Breakdown Maintenance (From reference [21]) where the system is maintained after a breakdown and Predictive Maintenance (From reference [22]) where maintenance operation applies only when required by the state of the system. Several principals of maintenance exist and some are described and need to be further evaluated in the coming work. - Condition Based Maintenance - Preventive Maintenance - Condition Monitoring - others
Different technologies to be used for maintenance and diagnostics shall be further investigated. SNMP is a quite known protocol for maintenance and managements and used in the area of telecommunication, others protocols to be considered: REST, etc.
GA 730640 Page 149 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Other areas shall be looked into such as maintenance and control systems from industry and electric power systems. Industry Standards for maintenance and maintainability have to be considered.
8.2. Scope - Motivation
In some cases - and wayside objects are one of these - there are systems where it is necessary to apply a special surveillance, gathering information about the state; it is commonly named as CBM (Condition Based Maintenance), where the maintenance actions are planned according to a functional data analysis of the assets to maintain Fehler! Verweisquelle konnte nicht gefunden werden.16]. This kind of maintenance has notable advantages over the preventive maintenance, but usually this technique involves high costs on labour and in continuous measurement systems. Condition Monitoring consists on a continuous functional parameter monitoring of a system/machine/asset, like temperatures, vibration, consumptions, etc. in order to find significant changes that involve wear and tear in the assets (From reference [16]). This type of maintenance allows planning corrective actions in advance to the failures and presents significant improvements against preventive maintenance, performing the corrective actions when the failure is detected (From reference [18]). Condition Based Maintenance Up to nowadays, CBM Maintenance has been described by two different operations: Isolated Measurement Systems that may be expensive and accurate and normally used as a protection system and Manual collection of measurements (From reference [16]). The information collected in a CBM Maintenance Model are classified into: direct information and indirect information. Direct information is where the information gathered directly determines the fault and indirect information needs and analysis with associated information, like a vibration frequency analysis (From reference [23]). On the other hand, inspections can be carried out continuously, periodically, or non-periodically (From reference [18]). Predictive Maintenance The high interconnection of objects and assets in systems expected for the next years leads us to an approach to maintenance and diagnosis based on Predictive Maintenance techniques. In a more detailed concept than the initial definition, Predictive Maintenance is the application of predictive algorithms gathering real time data in order to detect in advance failures before they occur and generate advice to maintainers to solve (From reference [16]). A Smart Wayside Object Controller is expected to provide continuous real time information about the state of the railway
GA 730640 Page 150 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models wayside objects – and from itself - and will lead the change in the wayside maintenance strategy due to the affordable costs that will be assumed by railways administrators. CBM Maintenance could be the leading cutting-edge to start the digital evolution to predictive railway wayside maintenance, acting as a roadmap towards to intelligent systems. A major share of the operating costs of any production system is related to maintenance costs, so therefore, the main mission is to obtain an optimal maintenance and diagnosis system to provide availability, reliability, and safety at the lower possible cost (Pham and Wang, 1996). This approach, apply to Smart Wayside Object Controller, where all wayside objects are connected in real time to the controller, will generate a challenge in railways maintenance policies and maintenance systems towards to Predictive Maintenance environments with a much affordable cost and will not necessarily be used as a means of protection. This evolution of CBM Maintenance to Predictive Maintenance has some challengers (From reference [25]), and by itself, in many cases, does not justify the investment and it is necessary to develop specific high level applications, which through advanced data analysis techniques are able to learn from monitored systems offering the state of assets deterioration and forecast failures helping maintainers to planning the system`s stops. So we will have to evaluate these matters and the main benefits related to Predictive Maintenance, which are: lower insurance rates, increased reliability, improved product quality, better asset protection, reduced catastrophic and unexpected failures, reduced spare parts inventory, reduced MTBF, increased asset life cycle and reduced energy consumption (From reference [26]). To end, as an example for a predictive maintenance application, we refer to the research document “Fault Diagnostics of Railway Point Machine” of the Nottingham Transportation Engineering Centre, where an online point machine condition monitoring system for railway point systems (switches) is described, based on the current measurements trends (high interconnections between systems), which would allow the maintainers to detect the faults at an earliest stage or prior to its happening. The main idea of this application is to analyse the data extracted from several Railways databases who are logging the current measurements of the point machines, like repairs and adjustments and any kind of information about it. Due to the consideration that fault detections is a pattern recognition problem, Support Vector Machines (SVM) are chosen for the analysis. For training and testing of the system, MATLAB is used to construct a binary SVM to classify normal or failure currents of the switches. SNMP Protocol
GA 730640 Page 151 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Another point to consider is based on the diagnostic systems. Most diagnostic systems used today are based on the SNMP Protocol which is commonly used in the telecommunication domain. The SNMP Protocol is the internet- standard protocol for IP network management used for asset monitoring, gathering information from network devices showing the information of the systems organized on a Management Information Base (MIB) that describes the configuration and the system status. This information could be queried remotely by management applications. SNMP also allows definition of so called “traps”. Traps could be configured to send messages from monitored devices to management applications triggered by configurable conditions, like a temperature increasing over a max value. As a well-used standard, most of the operating systems and network devices support SNMP, as well as third-party management software to monitor the status of assets and applications. Other protocols and interfaces have been included to complete the state-of-the-art in this matter. Scope For any equipment or new industrial system that is intended to research and perform a future development, it is necessary to carry out a study on the state-of-the-art, not only of the actual equipment at the functional level, but also of all the systems of its future operational environment. As is mentioned in the previous chapter, Maintenance and Diagnostic systems is a fundamental part of all railway operational system since the major operating costs of any production system are related to maintenance costs. Therefore it is necessary to study the state-of-the-art of Maintenance and Diagnostic systems in railways environments to determine what kind of maintenance policy is the most appropriate to maintain. The new system and, as it cannot be otherwise, if with the new functionalities of the system , in our case, the Smart Wayside Object Controller, it is possible to evolve the maintenance policy in a way that can improve maintenance operational costs. In a railway operational system, there are a lot of wayside elements (track circuits, axle counters, switches, balises, etc.) distributed along the rail interconnected with Objects Controllers. Most of them are maintained in a scheduled or preventive maintenance policy, due to the long distribution along the track, and others, like Object Controllers, maybe are maintained in a CBM policy given the connection they have to the Operational Control Centres. For scheduled or preventive maintenance policies in the railway domain - more explicitly over railway wayside objects - inspection cost is considerable (labour costs, specific test devices, and sometimes suspension of the operations). Normally, to reduce the risk of a failure, inspections are performed in short intervals which imply an even larger inspection cost.
GA 730640 Page 152 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Given the current scenario and, together with the Smart capability that is intended for the Smart Wayside Object Controller and its high interconnection; what is intended is to evolve the maintenance of the track equipment towards to a predictive maintenance approach where Smart Wayside Object Controller will be able to perform a fault detection on an earliest stage (for wayside objects and for itself) and trigger it to the Computerized Maintenance Management System (CMMS). In a second stage, in a cloud computing system/TMS/TMC Maintenance System, an advanced data analysis with all the collected data received from the Smart Wayside Object Controller will be performed to re-estimate the threshold boundaries and update it remotely (If this is the case) to the Smart Wayside Object Controllers. With this approach to predictive maintenance, it is expected that inspection intervals (scheduled maintenance) can be lengthened according to the estimated failure thresholds, contributing still more to a considerable reduction in costs. The security from several aspects shall be taken into account such as Cyber security, availability, and confidentiality (encryption). Requirements for remote configuration and access to controls for maintenance functions, e.g. restart shall be included and taken into account.
8.3. Research projects in the same scope
The Transforming Transport project (H2020 Project ID: 731932) deals with Big Data focus on Maintenance, it is not the same scope: we are part of the producers (producers & collectors of rail assets data), and the project it is focus on the consumer/final app, but a feedback to modify threshold, triggers, etc. for predictive maintenance in the lower layer (OC) could be useful.
8.3.1. Input from Infrastructure Innovation Program (IP3)
Connection to IP3 is also to be analysed concerning the current and future Wayside Objects definition Basically focus on the ITD – Intelligent Asset Management (Compose of IAMS, RIMMS and DRIMS) and in the enhanced/Next generation wayside objects.
8.4. Products – Results in the scope of the study
Products – patents in the same scope of the study
GA 730640 Page 153 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Company Product Detail
Bombardier OPTIFLO
Siemens Sidis W Compact point diagnostic System
Alstom Switch Points Monitor Transduce to diagnostic switch points (local)
Cactus Rail Cactus TMS Traffic management system
Cactus Rail Cactus CS Communication server that handles the information from various sources and object controllers
Cactus Rail Cactus C1m C10, C100 Object controllers of various capacity
ABB Asset Health Center Asset performance management
ABB Ellipse Select Enterprise asset management
AMT-SYBEX Fieldreach Mobile asset management
Table 8.1 – Products – patents in the same scope of the study
GA 730640 Page 154 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 8.5. Position of the competitors
Position of the competitors in the same scope
Company Product Detail
voestalpine Modular Diagnostic System - A modular diagnostic system PHOENIX MDS for a scalable and cost efficient structuring of wayside monitoring systems.
voestalpine Rail Crossing Monitoring - RXM solutions automatically RXM detect crossing faults and assist investigation work.
voestalpine Signaling Power Monitoring - With SPM operators can find SPM and fix power problems before performance is affected.
voestalpine Switch Condition Monitoring - SCM enables operators to SCM reduce switch failures and optimise maintenance processes.
voestalpine Track Circuit Monitoring - TCM systems can predict TCM track circuit failures and capture intermittent faults.
Table 8.2 – Position of the competitors in the same scope
GA 730640 Page 155 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 8.6. Interfaces (network, protocol, capacity, etc.)
In railways the data communication between centrally located equipment, e.g. an interlocking, object controllers and field elements currently often use proprietary communication protocols. Signalling and maintenance functions may also share the same communication channel and the same (proprietary) protocol. In the telecommunications domain, which in general is more advanced in terms of standardization than the railway domain, there exists a standard protocol for network management. This protocol could be a candidate to use for management and maintenance functionality in a ‘Smart Wayside Object Controller’. Other systems and standards exist and are used in other domains for information exchange between systems, which also could be used for Object controllers:
· MQTT (Message Queue Telemetry Transport) is a standard adapted for connections with remote locations and limited band width mainly in the IoT scope.
· CoAP (Constrained Application Protocol) is a web transfer protocol for machine to machine applications. Designed to be used when constraints in nodes and networks.
· OPC-UA is well spread and used both in industry and IT-communication systems for connection to overall supervision and maintenance systems. It could be a one of the standards to be recommended for connection of Object Controller.
· DDS (Data Distribution Service) is an Object Management Group (OMG) machine-to- machine (sometimes called middleware) standard that aims to enable scalable, real-time, dependable, high-performance and interoperable data exchanges using a publish– subscribe pattern.
· SSI (Synchronous Serial Interface) is a widely used serial interface standard for industrial applications between a master (e.g. controller) and a slave (e.g. sensor). SSI is based on RS-422[1] standards and has high protocol efficiency in addition to its implementation over various hardware platforms, making it very popular among sensor manufacturers.
· REST (Representational state transfer)or Restful web services is a way of providing interoperability between computer systems on the Internet. REST-compliant Web services allow requesting systems to access and manipulate textual representations of Web resources using a uniform and predefined set of stateless operations.
· SOAP (originally Simple Object Access Protocol) is a protocol specification for exchanging structured information in the implementation of web services in computer networks. Its
GA 730640 Page 156 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
purpose is to induce extensibility, neutrality and independence. It uses XML Information Set for its message format, and relies on application layer protocols, most often Hypertext Transfer Protocol (HTTP) or Simple Mail Transfer Protocol (SMTP), for message negotiation and transmission.
8.6.1. Simple Network Management Protocol (SNMP)
Simple Network Management Protocol (SNMP) is the Internet-standard protocol for handling managed devices on IP networks. It is used for configuring and collecting information from network devices, such as servers, printers, switches, routers and more. The protocol is also widely used for network monitoring. SNMP exposes management data in the form of variables on the managed systems organized in a management information base (MIB), which describe the system status and configuration. These variables can then be remotely queried by a managing application.
Figure 8.1 – SNMP Components
SNMP also allows definition of so called ‘traps’. A ‘trap’ can be configured to send a message from the managed device (e.g. the ‘Smart Wayside Object Controller) to a destination (e.g. the managing application) triggered by a configurable condition (e.g. a temperature increases over a max value). As SNMP is a well-used standard there is support for SNMP in most operating systems and there is a large number of third-party SNMP management software to monitor the status of managed devices and applications. GA 730640 Page 157 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Three significant versions of SNMP have been developed and deployed. - SNMPv1 is the original version of the protocol. - SNMPv2 (with variants) includes improvements in the areas of performance, security, confidentiality, and manager-to-manager communications. - SNMPv3, adds further security, e.g. with encryption. SNMP is a component of the Internet Protocol Suite as defined by the Internet Engineering Task Force (IETF). It consists of a set of standards (RFCs) for network management, including an application layer protocol, a database schema, and a set of data objects. Examples of SNMP usage: - Switch on or off a function in a device. - Enable an alarm (‘trap’) to be sent if a temperature is too high. - Enable an alarm to be sent if the secondary power source is lost. - Read an (digitized) analogue value from a device, e.g. voltage. - Read counters, that counts e.g. number of sent/received messages, number of errors etc. since last readout. Management Information Base (MIB) A management information base (MIB) is the database associated with SNMP. The database is hierarchical (tree-structured) and each entry is addressed through an object identifier (OID). The information is grouped into specific sets of data containing related information, e.g. about status of a Switch’s Ethernet interfaces, about connected equipment to a device (called Bridge- MIB), data and error counters for the TCP protocol etc. The structure of the MIB is discussed in several RFCs, especially RFC 1155, "Structure and Identification of Management Information for TCP/IP based internets". Examples of how SNMP could be used in Maintenance and Diagnostics:
· Defining alarms (‘traps’) that are triggered by an event or passing a limit. E.g. a communication port stops working, or a voltage is too low.
Periodically reading an error counter (e.g. communication port ok/faulty, or data packet lost) makes it possible to detect intermittent faults if the error rate (faults/time) is over a set limit.
GA 730640 Page 158 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 8.7. Inputs from other projects/domains
Several systems and standards exist and are used in other domains for information exchange between systems, which also could be used for Object controllers: MQTT, CoAP, DDS, SSI, REST and SOAP.
8.8. Result of the analysis
Maintenance and Diagnostic systems is a fundamental part of all railway operational system since the major operating costs of any production system are related to maintenance costs. In a railway operational system, there are a lot of wayside elements (track circuits, axle counters, switches, balises, etc.) distributed along the rail connected with Objects Controllers. Today most of them are maintained in a scheduled or preventive maintenance policy. Several principles of maintenance exist such as Condition Based Maintenance and Predictive Maintenance and need to be further evaluated in the coming work. Maintainability of the product is the essence to assure the remote operability provided by the wireless capability (power, wireless connection). Digitalization of the Railway enable analysis of collected data from multiple sources, Wayside object and Smart Wayside Object are important data sources. Advanced analysis with multi- source data can help find root causes of errors and lack of functions. Furthermore, it will contribute to improve predictive maintenance and high availability of the railway system.
GA 730640 Page 159 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 9. Conclusions
The objective of the analysis of the existing lines and economic model from the perspective of the wayside objects is to demonstrate the soundness of the concept of Smart Wayside Object Controller (SWOC) realizing a distributed approach to rail automation. After the analysis completed in this document the possibility of decentralized Smart Wayside Object Controllers is reassured, as real solutions have been given for wireless communication, power supply and maintenance and diagnosis. The analysis of the impact on different economic indicators (CAPEX, OPEX) suggests that Regional Rail lines are the most convenient scenario where the proposal of SWOC is a priori approachable in technical and economic terms. Distributed wireless SWOC solution copes with the challenges of the new projects and innovations mainly on complex rail topologies with a high/medium number of stations: predictive maintenance, degradation laws, fail-safe solutions, advanced train positioning technologies, distributed solutions that reduced the global solution, wireless solutions (for both networks and energy), and reducing delays/downtime in the infrastructure. The absence of cables, the distributed solution and the necessary intelligence of these SWOCs (basic intelligence for automations, communication between neighbours, and predictive maintenance) should be and indispensable set of features of future fail-safe OC solutions
In order to obtain wireless connection different options are available, and it is necessary to differentiate the wireless technologies based on application: safety critical applications and non-safety critical, pursuant to timing latency, data bandwidth and power consumption requirements.
There are many existing and coming possibilities to ensure the energy supply to a “self- sufficient Smart Wayside Object Controller”. A specific solution for power supply will depend on actual consumption, which in turn depends on the configuration and power consumption of the object controller, on the environmental conditions for energy harvesting and on the mode of the railway line operation. Reduction of the power consumption will be a part of new generations of technology.
Maintenance and diagnosis systems are a fundamental part of all railway operational systems since the major operating costs of any production system are related to maintenance costs. Therefore maintainability of the product is the essence to assure the remote operability provided by the wireless capability (power, wireless connection). Advanced maintenance and diagnosis techniques have to be applied to SWOC and all wayside objects.
GA 730640 Page 160 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
Considering all the above conclusions a modular solution should be the most appropriate for the SWOC to provide flexibility, to allow for easy Wayside Object implementation, therefore the complete solution should be a balance and compromise of the following different aspects:
· Solution of wireless connectivity. · Solution of power supply: energy harvesting and optimized power consumption. · Solution of maintenance and diagnosis.
The most promising solutions are proposed as further basis to our project to be applied in the SWOC definition and to be specified in detail for the demonstrator including safety and security aspects.
GA 730640 Page 161 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 10. References
No Reference
1 ERRAC, “Research and Innovation – Advancing the European Railway, Future of Surface Transport Research Rail, Technology and Innovation Roadmaps”, 2016
2 UIC, “A Global Vision for Railway Development”, 2015
3 Wikipedia
4 EU FP7 project NGTC – Next Generation Train Control, grant nr. 605402 Deliverables D6.2 – D6.6 of the WP6
5 GSMA Intelligence Understanding 5G: Perspectives on future technological advancements in mobile
6 Battery University http://batteryuniversity.com/
7 Capacitor Guide http://www.capacitorguide.com/
8 IEC White Paper about Electrical Energy Storage http://www.iec.ch/whitepaper/energystorage/
9 Example of re-injection of energy.
HESOP - PRODUCT SHEET - ENG - OCT 2015.pdf
10 Example of power supply system.
2012_09_13_Micro_ Midi_Hybrox_portfolio_standard_v2.pdf
11 Innowattech Alternative Energy Harvesting System Railways Solution
GA 730640 Page 162 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
https://www.youtube.com/watch?v=CfnyJ0_XarI
12 EU FP7 project MERLIN. Sustainable and intelligent management of energy for smarter railway systems in Europe: an integrated optimization approach, D1.1 Railway network key elements and main sub-systems specification. http://www.merlin-rail.eu/wp-content/uploads/2012/12/MRL-WP1-D-ANS-013-06- D1_1-Railway_network_key_elements_and_main_sub-systems_specification.pdf http://www.merlin-rail.eu/
13 EU FP7 project OSIRIS, Optimal Strategy to Innovate and Reduce energy consumption in urban rail Systems D4.1. Smart grid system definition, system studies and modeling, technologies”, 2013 http://www.osirisrail.eu/wp- content/uploads/2015/01/D4.1_Smart_grid_system_definition_system_studies_and_m odeling_technologies_evaluation.pdf http://www.osirisrail.eu/
14 Energy Harvesting Systems Design for Railroad Safety”, A thesis presented at the University of Nebraska-Lincoln, Abolfazl Pourghodrat. http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1023&context=mechengdiss
15 A guide to Understanding Battery Specifications http://mit.edu/evt/summary_battery_specifications.pdf
16 SANCHEZ Alfredo, Internet de las cosas, Industria 4.0 y Mantenimiento Industrial. Nov. 2016. Available online. ZEQUEIRA R.I, BÉRENGUER C., Optimal Inspection policies with predictive and preventive 17 maintenance. 2007. Available online.
18 GOLMAKANI H.R, Condition-based inspection scheme for condition-based maintenance. 2011. Available online
19 VILEINISKIS Marius, REMENYTE-PRESCOTT Rasa Dr. Fault Diagnostics of Railways Point Machines. 2012. Available online
20 Zhao, 2003; and Ahmad and Kamaruddin, 2012
GA 730640 Page 163 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models
21 Bevilacqua and Braglia, 2000
22 Chu et al., 1998; Dieulle et al., 2001; and Moya, 2004
23 Christer and Wang 1995 Raheja et al. 2006
24 Pham and Wang, 1996
25 Tan and Raghvan 2010
26 Christer et al., 1997; Kakkar, 1999; Beltran and Lopez, 2000; Lupinucci et al., 2000; Villar et al., 2000; and Carnero, 2006
27 ZigBee Alliance pages – www.zigbee.org
28 Radio-Electronics.com online journal – http://www.radio-electronics.com
29 FreeWimaxInfo.com portal – http://freewimaxinfo.com/
30 Sigma Design company web pages – http://www.sigmadesigns.com/
31 EnOcean company web pages – https://www.enocean.com/en/
32 LoRa Alliance web pages – https://www.lora-alliance.org/
33 Link Labs company web pages – https://www.link-labs.com/
34 SigFox company web pages – https://www.sigfox.com/en
35 EULYNX – www.eulynx.eu
GA 730640 Page 164 of 165 X2Rail-1 Deliverable D7.1 Analysis of existing lines and economic models 11. Appendices
None
GA 730640 Page 165 of 165