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Download/Upload Level Model University of Bradford eThesis This thesis is hosted in Bradford Scholars – The University of Bradford Open Access repository. Visit the repository for full metadata or to contact the repository team © University of Bradford. This work is licenced for reuse under a Creative Commons Licence. MOBILE MULTIMEDIA SERVICE PROVISIONING WITH COLLECTIVE TERMINALS IN BROADBAND SATELLITE NETWORKS M. HOLZBOCK PhD 2011 MOBILE MULTIMEDIA SERVICE PROVISIONING WITH COLLECTIVE TERMINALS IN BROADBAND SATELLITE NETWORKS An approach for systematic satellite communication system design for service provisioning to collective mobile terminals including: mobile satellite channel modelling, antenna pointing, hierarchical multi-service dimensioning and aeronautical system dimensioning Matthias HOLZBOCK submitted for the degree Doctor of Philosophy School of Engineering, Design and Technology University of Bradford 2011 Name: Matthias Holzbock Title: Mobile Multimedia Service Provisioning with Collective Terminals in Broadband Satel- lite Network Keywords: mobile, satellite, service, channel, collective, group, dimensioning, antenna, pointing Abstract: This work deals with provisioning of communication services via satellites for collec- tively mobile user groups in a heterogeneous network with several radio access tech- nologies. The extended use of personalised user equipment beyond the coverage of one single terrestrial network by means of a satellite transport link, represents an increas- ingly important trend in mobile satellite communication. This trend is confirmed by the commercial introduction of broadband satellite communication to mobile terminals mounted on vehicles, trains, ships or aircraft. This work provides a consequent and structured approach for provisioning of services to broadband satellite terminals for mobile user groups and addresses: ² a systematic satellite communication system design process for collective mobile terminals; ² mobile satellite modelling at a wide range of frequencies, including current and potential frequencies; ² an optimised Pointing Acquisition and Tracking (PAT) system design including characterisation of moments for vehicle types of all mobile scenarios; ² a general hierarchical multi-service dimensioning methodology for collectively mobile user groups, including voice, data, and multimedia services; ² an aeronautical system dimensioning scheme with (capacity and handover) re- quirements analysis and evaluation of results for different satellite scenarios. Contents 1 Introduction 1 1.1 Mobile Communications - a Satellite Opportunity . 1 1.2 Mobile Satellite Terminals for Collective Use - Scope of the Thesis . 5 1.3 Objectives and Contributions of the Thesis . 8 1.3.1 Mobile Satellite Channel . 9 1.3.2 Mobile Terminal Pointing, Acquisition and Tracking (PAT) . 10 1.3.3 System Dimensioning for Collective Mobile Terminals . 12 2 Satellite Communications Fundamentals for Mobile Services 14 2.1 Satellite - Terminal Geometry . 15 2.1.1 Satellite Orbits . 15 2.1.2 Satellite to Mobile Basic Geometric Relations . 17 2.1.3 Coverage Area and Constellation Parameters . 21 2.1.4 Spot Beam Concept . 23 2.2 Satellite - Mobile Radio Link . 27 2.2.1 Antenna Radiation Pattern and Directivity . 27 2.2.2 Boresight, Look Direction and Off Boresight Angle . 29 I CONTENTS II 2.2.3 Gain and Efficiency . 29 2.2.4 Beamwidth and Beam Contour . 31 2.2.5 Radio Link System . 32 2.2.6 Noise and Interference . 33 2.3 Regulations for Mobile Earth Stations . 35 2.3.1 Aircraft . 37 2.3.2 Maritime . 39 2.3.3 Land mobile Train . 39 2.4 Characteristics of the Mobile Satellite Channel . 41 2.4.1 Physical Phenomena of the Radio Channel . 41 2.4.2 Influences of Terminal Mobility on the Satellite Channel . 42 2.4.3 Mobile Channel Characterisation . 47 2.4.4 Lutz Channel Model . 50 2.5 Literature . 52 2.5.1 Mobile Satellite Channel . 52 2.5.2 Satellite Terminal Antenna Pointing, Tracking and Acquisition . 54 2.5.3 System Dimensioning for Collective Mobile Satellite Terminals 55 3 Mobile Satellite Channel 57 3.1 S Band LMS Channel Characterisation by Measurement . 59 3.1.1 S Band LMS Channel Measurement Setup . 59 3.1.2 S Band LMS Channel Measurement Results and Parameters . 67 CONTENTS III 3.2 EHF Band LMS Channel Characterisation by Measurement . 69 3.2.1 EHF Band LMS Channel Measurement Setup . 70 3.2.2 EHF Band LMS Channel Measurement Results and Parameters 72 3.3 Dominant Characteristics of LMS Channels at Higher Frequencies . 74 3.3.1 Outage Maps of Satellite Visibility . 76 3.3.2 Results and Comparison with Statistically Derived Parameters . 80 3.3.3 Azimuth Diversity . 82 3.4 Ka Band Aeronautical Satellite Channel Characterisation by Measure- ments . 83 3.4.1 Ka Band Aero Satellite Channel Measurement Setup . 83 3.4.2 Ka Band Aero Satellite Channel Measurement Results and Pa- rameters . 86 3.5 Dominant Characteristics of Aeronautical Satellite Channels at Higher Frequencies . 87 3.5.1 Aircraft Structure Shadowing . 87 3.5.2 Cloud and Rain Attenuation . 90 3.6 Conclusions . 95 4 Satellite Terminal Antenna Pointing, Tracking and Acquisition 97 4.1 PAT Basics and Definitions . 98 4.1.1 PAT Problem . 98 4.1.2 Definitions . 99 4.1.3 PAT Design Methodology . 100 CONTENTS IV 4.2 Beam Agility Requirements of the Terminal Antenna . 102 4.2.1 Satellite Dynamics . 102 4.2.2 Agility of Mobile Terminals . 103 4.3 Antenna Beam Steering . 112 4.3.1 Mechanically Steered Antennas . 113 4.3.2 Electronically Steered Antennas . 115 4.3.3 Beam Steering Technology Tradeoff . 117 4.4 PAT Algorithms . 120 4.4.1 Closed Loop PAT . 120 4.4.2 Open Loop PAT . 124 4.4.3 PAT Algorithms Tradeoff . 125 4.5 PAT Errors . 126 4.5.1 Azimuth and Elevation Errors . 126 4.5.2 Polarisation Error . 132 4.5.3 Latency Error . 136 4.6 PAT Solutions for Different Environments . 137 4.6.1 Assessment of PAT Solutions for Different Environments . 137 4.6.2 Open Loop Vehicular PAT Implementation . 139 4.6.3 Aeronautical INS Based Open Loop vs. Conical Scan Closed Loop PAT Implementation . 141 4.6.4 Vehicular Low Cost PAT Implementation . 144 4.7 Conclusions . 152 CONTENTS V 5 System Dimensioning for Collective Mobile Satellite Terminals 155 5.1 Methodology of Hierarchical System Dimensioning . 156 5.1.1 Methodology - Service Mix, Models and Usage . 159 5.1.2 Methodology - User Group Size and Mobile Terminal Traffic . 161 5.1.3 Methodology - Satellite Scenario and User Group Distribution . 162 5.1.4 Methodology - Capacity and Handover Analysis . 164 5.2 Numerical Example - Aeronautical System Dimensioning . 167 5.2.1 Aeronautical Example - Service Mix, Models and Usage . 167 5.2.2 Aeronautical Example - User Group Size and Mobile Terminal Traffic . 172 5.2.3 Satellite Scenario and User Group Distribution . 174 5.2.4 Aeronautical Example - Data Traffic Analysis . 179 5.2.5 Aeronautical Example - Handover Analysis . 182 5.3 Assessment of Satellite System Concepts for Aeronautical Communi- cation . 188 5.3.1 Coverage Optimisation . 188 5.3.2 Handover vs. Capacity Optimisation . 190 5.4 Conclusions . 194 6 Summary 197 A Acronyms 206 B Notation and Symbols 214 CONTENTS VI C Transformations 218 C.1 Earth - Mobile - IMU - Antenna Coordinate Transformation . 218 C.1.1 Earth Fixed Coordinates E . 219 C.1.2 Local Coordinates L . 219 C.1.3 Inertial Measurement Unit Coordinates I . 220 C.1.4 Antenna Coordinates A . 221 C.2 Polarisation Transformation . 222 D Traffic Models 225 D.1 Web Browsing . 225 D.1.1 Packet Level Model . 225 D.1.2 Page Level Model . 227 D.2 Email . 229 D.2.1 Packet Level Model . 229 D.2.2 Email Download/Upload Level Model . 229 D.3 Voice . 231 D.3.1 Packet Level Model . 231 D.3.2 Call Level Model . 231 Bibliography 233 Chapter 1 Introduction 1.1 Mobile Communications - a Satellite Opportunity Satellite Communications Satellites offer mobile services to users since the late 1970s. Starting from Inmarsat’s first maritime applications via geostationary earth orbit (GEO) satellites, today the systems for mobile communication range from single GEO satellites to sophisticated constellation networks with interconnected, regenerative satellites (e.g., Iridium [Vat91], [Bru96]). While in the pioneering decades the commu- nication companies were mostly governmentally held, nowadays telecom and satellite companies are privatised providers, which have to operate in a highly competitive mar- ket. In this competition, unfortunately only a few mobile satellite service (MSS) systems turned out to be successful from a market perspective. The discussions about share of resources, namely frequency spectrum allocation, have witnessed a shift towards the strong arguments of the commercially more successful terrestrial mobile market. Nevertheless, satellite communication features the inherent strength of wide area cov- erage and as a consequence they are excellently suited or even indispensable for the provision of service to globally scattered users. Bearing these strengths in mind, an advantageous integration with terrestrial systems is the ultimate goal. 1 CHAPTER 1. Introduction 2 Terrestrial mobile communication systems of the 2nd generation were initially deployed regionally with incompatible standards being concentrated on areas of high population and service penetration. With this background, first attempts for worldwide personal communication by satellites like Iridium or Globalstar [WV93], [Sch95] were made. Using low earth orbit (LEO) satellite constellations, these systems (assembled some- times by the naming “big LEOs”) have been proposed in the beginning of the 1990s and became operational
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