Galileo Workshop 2021: All You Need to Know About Europe's GNSS

Galileo Workshop 2021: All you need to know about Europe’s GNSS performance GRC Webinar Peter BUIST, Marco PORRETTA, Lennard HUISMAN, Andrea NARDO, GSA-GRC

03.03.2021 – Noordwijk (NL), GSA-GAL-GRC-PFR-A10233 • Agenda

• (14H00)Introduction (Alvaro MOZO, GSA, Hillar TORK, EC) • (14h10) Overview Galileo, Service provision and GRC (Peter BUIST, GSA-GRC) • Monitoring and assessment guidelines ‒ (14h30) Service Definition Document and Minimum Performance Levels (Marco PORRETTA, GSA-GRC) ‒ (14h50) Performance monitoring and assessment needs (Lennard HUISMAN, GSA-GRC) ‒ (15h10) Reference products generation (Andrea NARDO, GSA-GRC) ‒ Q&A • Service performance monitoring ‒ (15h45) GRC (Marco PORRETTA, Peter BUIST) ‒ (16h05) ESA (Gaetano GALLUZZO) ‒ (16h25) Geodetic Observatory of Pecny (Jan DOUSA) ‒ (16h40) CNES (Bernard BONHOURE) ‒ (16h55) NLR, FGI and Chalmers (Hein ZELLE & Heiko ENGWERDA) ‒ Session summary (GSA) ‒ Q&A 2 • (17h25) Conclusions (Alvaro MOZO, GSA, Hillar TORK, EC) Overview Galileo, Service Provision and the GRC Galileo Workshop 2021: All you need to know about Europe’s GNSS performance Peter BUIST, GSA-GRC

03.03.2021 – Noordwijk (NL) 3 Galileo Today

• 2 Galileo Control Centres (GCC) in Germany and Italy • 2 Galileo Security Monitoring Centres (GSMC) in France and Spain • 1 Galileo SAR Centre (SGSC) in France • Galileo Reference Centre (GRC) in the Netherlands • GNSS Service Centre (GSC) in Spain • 13 sensor stations, 5 uplink stations, 6 telemetry and command stations, 3 MEOLUT’s around the world • 26 satellites on-orbit occupying all reference slots • … and many other facilities (e.g. TSP, GRSP)

GSA-GAL-GRC-PFR-A10233 4 Galileo Constellation Status

Navigation Payload (22 Operational + 2 contributing)

26 satellites in orbit 2 L3 SC now contributing to OS 1 spare (GSAT0204) 1 unavailable (GSAT0104)

Search and Rescue Payload (24 in service) 2 out of 26 satellites with no SAR Transponder (by design)

“0” 5 unoccupied reference slots

GSA-GAL-GRC-PFR-A10233 5 Galileo Ground Segment Status

13 GSS 5 ULS 6 TTCF

GSA-GAL-GRC-PFR-A10233 6 Galileo Service Provision

• L3 (E14 & E18) )satellites in operational constellation as “auxiliary” satellites • Second operational centre for GSMC activities entry into operations • Launch 11 preparation EOP and IOT under responsibility of GSA with GSOp Security Monitoring under responsibility of GSA • Improvement of System robustness ongoing • Site evolutions Extension of GCCs and GSMC-FR for FOC ongoing Extension of Galileo Robust Operational Network (GRON) Installation of new GSS sites in the Pacific and Caribbean area ongoing

Installation of new MEOLUT in India Ocean area ongoing 7 Galileo Services Documentation

The GSC is the portal making available to the user communities the Programme reference documents for the Open and SAR services:

Galileo – Open Service Galileo – Open Service SiS Interface Control Document Service Definition Document

Ionospheric Correction Algorithm for Galileo – Search and Rescue Service Definition Document Galileo Single Frequency Users (including new Galileo Return Link Service) 8 High Accuracy & Authentication

• High Accuracy Service based on PPP transmission in E6B ‒ Gradual introduction (regional/global, accuracy target, convergence time…) ‒ Free of charge ‒ ICD under final consolidation • Navigation Message Authentication ‒ Integrated in E1 OS ‒ Free of charge ‒ OS-NMA Public Testing 2021 • Commercial Service Authentication ‒ E6C Spreading Code Encryption

GSA-GAL-GRC-PFR-A10233 9 GRC Mission

• Perform independent monitoring and assessment of service provision • When feasible, assess the compatibility and interoperability between Galileo and other GNSS • Provide service performance expertise to Programme • Support investigations of service performance and service degradations • Archive service performance data over nominal operational lifetime of system • Integrate data and products from EU Member States, Norway and Switzerland (MS)

GSA-GAL-GRC-PFR-A10233 10 GRC Architecture and Operational Concept

• Fully independent of the system and of the Galileo Service Operator (GSOp) ‒ both technical solution and operations • Automatic processes for continuous monitoring and data processing ‒ each Galileo service shall be monitored against Key Performance Indicators (KPIs) and Figures of Merit ‒ KPIs are derived from SDDs and Galileo Service Operator KPIs • Evaluate basic monitoring parameters for Galileo signals against values specified in Galileo SiS ICD • Perform dedicated campaign-based analyses ‒ Also taking advantage of data, products, facilities and expertise contributed by MS

GSA-GAL-GRC-PFR-A10233 11 Galileo Service performance monitoring

Service Provider

GSA, under EC delegation

Galileo Service Galileo Reference Operator Center Contractor GSA + Contractor + MS

Routine / KPI Routine and On- Reporting Demand Reporting

GSA-GAL-GRC-PFR-A10233 12 GSA - GAL Concept GRC Architecture and Operational - GRC - PFR Core Facility - A10233 • • capabilities Stand Netherlands Situated - alone in in the

MS Contributions • • • Expertise Products Data 13 GRC Implementation Approach

• Main source of input KPIs reporting complemented with MS reports • Support OS-NMA and HAS validation • Expending the number of KPIs for Enhanced Services • Flexibility to address additional KPI monitoring ‒ Aviation (for EASA and Eurocontrol) ‒ Maritime ‒ Rail/Road ‒ Other • GRC v1.1 Operational, includes Galileo, GPS, Glonass and Beidou

GSA-GAL-GRC-PFR-A10233 14 GRC Architecture and Operational Concept

class GRC Logical View

GRC

Raw Data Monitoring and Acquisition Control

Reference Data Management Products Function Generation Serv ice Performance Monitoring

GSA-GAL-GRC-PFR-A10233 15 GRC Architecture and Operational Concept

GSA-GAL-GRC-PFR-A10233 16 GRC V1

GSA-GAL-GRC-PFR-A10233 17 GRC Interfaces

Reference stations • Binary data ‒ GRC network ‒ GESS network ‒ MS (CNES Regina)

• RINEX data ‒ Including stations mentioned above ‒ >100 MS stations (word wide and regional) ‒ IGS

GSA-GAL-GRC-PFR-A10233 18 Member States’ Contributions to the GRC

• 23 organisations from 14 countries • Including ‒ Worldwide network of reference stations ‒ Reference products ‒ Timing labs ‒ Radio telescopes ‒ Laser ranging ‒ Vehicles, vessels and airplanes

GSA-GAL-GRC-PFR-A10233 19 GRC Sensors, data and products

Ionosphere Product (Latency) Precise orbits /clocks Code biases Maps GRC & external provider GRC & external provider GRC Final (5 - 18 days) MS MS MS IGS MGEX IGS MGEX IGS (Combined) GRC GRC GRC Rapid (12 - 48 hours) MS IGS MGEX IGS MGEX IGS (Combined) GRC Ultra Rapid (3 hours) MS Reference station observation Merged broadcast Observation data (Latency) data ephemeris GRC Sensors Institute GRC & GESS GRC & GESS Automotive GNSS sensors University of Trieste Daily RINEX (3hours) MS Global and regional networks MS Global network University of Porto IGS IGS Airborne GNSS sensors NLR GRC & GESS GRC & GESS Hourly RINEX (15 min - 2 MS Global and regional networks MS Global network Marine GNSS sensors Romanian Space Agency hours) IGS IGS Signal in Space sensors ASTRON & Chalmers GRC & GESS GRC & GESS Near real time Binary (15 MS Global network min) Satellite Laser Ranging FGI IGS

GSA-GAL-GRC-PFR-A10233 20 Monthly KPI Report cross-check

KPI Database

KPI Comparision GSOp/SDDs/MS Parser Discrepancy products/other GNSS Comparison report

GRC products KPI (Core and MS) Generator

GRC issue Investigation

Approved report

GSA-GAL-GRC-PFR-A10233 21 Monthly Report-1

• For internal Programme use • Delivered monthly, covering Galileo performances for 1 month • Latency of 3 weeks ‒ Time needed to obtain final orbit, clock and bias products • KPIs reported: ‒ Ranging accuracy: Difference between the true satellite position and the one broadcast by the navigation message ‒ Ranging availability: Percentage of time that a satellite is transmitting a healthy signal, and percentage of time that a user is receiving at least one healthy signal ‒ UTC-GST, GGTO dissemination availability ‒ UTC-GST, GGTO offset/frequency accuracy • Complemented with MS reports • Main source of information for public quarterly report

GSA-GAL-GRC-PFR-A10233 22 GRC Performance & cross check reports Contribution to International GNSS Monitoring

• Authoritative international GNSS monitoring and assessment system to benchmark the performance of available GNSSs (GPS, Glonass, Beidou, Galileo) • Organized through the International GNSS Monitoring and Assessment Task Force of the United Nations Office of Outer Space Affairs, International Committee on GNSS • Nominated Monitoring Analysis Centre for Galileo is the GRC. ‒ European participation was confirmed by letter during ICG in Sochi 2016 • Similar topic are discussed as todays webinar between service providers from EU, US, Russia, China, Japan, India

GSA-GAL-GRC-PFR-A10233 24 Linking space to user needs

How to get in touch: www.GSA.europa.eu

EGNOS-portal.eu GSC-europa.eu G UseGalileo.eu

25 GAL OS SDD and MPLs Galileo Workshop 2021: All you need to know about Europe’s GNSS performance Marco PORRETTA, GSA-GRC

03.03.2021 – Noordwijk (NL) 26 Monitoring and assessment guidelines

• For this topic, the key document is the Galileo OS SDD (v1.1), which indicates: ‒ What is the Galileo OS; ‒ Terms and conditions of the service; ‒ Minimum Performance Levels (MPLs); and ‒ The conditions (“Usage Assumptions”) under which the MPLs can be reached.

GSA-GAL-GRC-PFR-A10233 27 Usage Assumptions

• The user receiver follows the GAL OS SIS ICD. ‒ “This OS SDD assumes that the Galileo OS user receiver complies with the technical requirements related to the interface between the Space Segment and Galileo OS receivers as established by the Galileo OS SIS ICD (Annex A [1]). The use of aiding sensors or systems is not considered.” • Only Healthy SIS observations are used: ‒ “The Galileo OS Minimum Performance Levels reported in the Galileo OS SDD refer exclusively to Healthy SIS. No MPL is defined for Unhealthy or Marginal SIS.” • Only the most recent navigation messages are used, with an Age of Ephemeris (AOE) < 4h: ‒ “[…] receivers must retrieve the values of navigation parameters relevant to the type of navigation solution to be computed from the most recent navigation data set broadcast on a Healthy SIS by the Galileo system after the start of the current receiver operation.” ‒ “The navigation solution is expected to meet the Minimum Performance Levels only if receivers do not use navigation parameters beyond their broadcast period. The maximum nominal broadcast period of a healthy navigation message data set is currently 4 hours. […] The AOE can be checked by the user.”

GSA-GAL-GRC-PFR-A10233 28 SIS flags to be checked

The SIS flags to be checked by the users depend on the specific service (SF or DF)

Galileo SIS flags (left), checks to be made for each service (centre), and example of a decision tree for a SF service (right) GSA-GAL-GRC-PFR-A10233 29 Excluded Errors

• Only Error contributions that are under the direct control of the Galileo system (SVs’ ephemeris and clock errors) are considered in the MPLs computation. ‒ “The MPLs […] do not take into account any error source that is not under direct control of the Galileo system. Specifically excluded errors comprise those due to the effects of: ‒ Signal distortion caused by ionospheric and/or tropospheric propagation effects. ‒ Residual receiver ionospheric delay compensation errors. ‒ Residual receiver tropospheric delay compensation errors. ‒ Receiver noise (including received signal power and interference power) and resolution. ‒ Receiver hardware/software faults. ‒ Multipath and receiver multipath mitigation. ‒ User antenna effects. ‒ Receiver operator error.”

GSA-GAL-GRC-PFR-A10233 30 SIS Ranging Accuracy

• Ranging Error characterization: ‒ Errors that are under direct control of the Galileo system: captured by the Signal-in-Space Ranging Error (SISE). ‒ Excluded errors: captured by the User Equipment Error (UEE). ‒ Both the SISE and the UEE form the User Equivalent Ranging Error (UERE). • The Signal-in-Space Ranging Accuracy is based on the SISE, which is the system contribution (SVs’ ephemeris and clock errors) to the UERE. • The instantaneous SISE depends on the user-to-satellite geometry. ‒ “The SISE inside the satellite footprint is typically characterized either as a Global Average or as the SISE at the Worst User Location (WUL)” • Reference Products are needed for the evaluation of the instantaneous SISE. ‒ “The instantaneous SISE is computed as the difference between the predicted satellite position and time, based on the broadcast navigation message, with a posteriori precise clock and orbit estimations.”

GSA-GAL-GRC-PFR-A10233 31 Use of Reference Products: Major Issues

The Quality of Reference Products has a direct impact on the quality of the SISE estimation Issue Reference Product Broadcast Product Comment SV Orbit Referenced to the SV Referenced to the Antenna The conversion COM2APC requires: Center of Mass (COM) Phase Centre (APC), for a • The definition of a local reference frame for the given signal or combination SV; of signals. • The use of an attitude law (which is also valid during eclipse periods); and the • The use of ANTEX files information (Phase Center Offset, PCO, and Phase Center Variations, PCV). SV Clock Referenced to an internal Referenced to the Galileo The bias between the internal time scale and the GST time scale (e.g. the GPS System Time (GST), which must be estimated and removed in the evaluation of Time, GPST). is not accessible to the the clock error. Reference Products • A possible technique to estimate this bias is based Provider. on the computation, at every epoch, of the average of the reference clocks over all the SVs.

GSA-GAL-GRC-PFR-A10233 32 SIS Ranging Accuracy Galileo SIS Ranging Accuracy MPL for any satellite (left) and over all satellites (right)

GSA-GAL-GRC-PFR-A10233 33 UTC: Dissemination and Determination Determination: Total Uncertainty in UTC estimation – Dissemination: GST-UTC (only) estimation accuracy

GSA-GAL-GRC-PFR-A10233 34 UTC Time and Freq. Dissemination Acc. Galileo SIS UTC Time (left) and Frequency (right) Dissemination Accuracy

A reference product is needed for the (GST-UTC) offset. This normally requires: • A calibrated receiver; • A connection to a Timing Laboratory; and • BIPM information.

GSA-GAL-GRC-PFR-A10233 35 Per-Slot and UTC Time Diss. Avail. Per-Slot (left) and UTC Time (right) Dissemination Availability

“At any time, the Galileo constellation to be taken as reference is the one published by the GSC.”

GSA-GAL-GRC-PFR-A10233 36 PDOP Availability PDOP Availability MPL (left) and example for February 2019 (right)

GSA-GAL-GRC-PFR-A10233 37 Positioning Service Availability Positioning Service Availability at the Average User Location for SF (left) and DF (right) users

GSA-GAL-GRC-PFR-A10233 38 Positioning Service Availability Positioning Service Availability at the Worst User Location for SF (left) and DF (right) users

GSA-GAL-GRC-PFR-A10233 39 UTC Time Determination Service Avail. UTC Time Determination Service Availability for SF (left) and DF (right) users

40 Statistical Modelling of the PVT Accuracy

• Assumption: “Zero mean and normally distributed pseudo-range errors characterized by identical UERE for every pseudo-range.” • Under this assumption, the Horizontal, the Vertical, and the Timing Errors of the PVT solution are also normally distributed with a zero mean. Their standard deviations can be expressed as:

= ⁄ (The Timing Error is the error in the Receiver Clock Offset Estimation with regards to the GST)

GSA-GAL-GRC-PFR-A10233 41 Statistical Modelling of the PVT Accuracy

• If the receiver clock offset estimation (with regards to the GST) is done with a fixed receiver at a known location (“Time Transfer”), the std dev. of the Time Transfer Error is computed as:

= ⁄ = ⁄ 1⁄

‒ is the number of healthy SVs tracked by the user receiver. • Both system and non-system contributions shall be considered in the estimation of the overall User UTC time transfer error. The standard deviation of the User Total Uncertainty in the UTC Time Estimation (for a fixed receiver at a known location) is then evaluated as:

= + = ⁄ 1⁄ +

‒ is the std. dev. of the overall User UTC Error (it includes both system and non-system contributions).

‒ is the std. dev. of the UTC SIS Dissemination Error (it includes only system contributions).

GSA-GAL-GRC-PFR-A10233 42 Statistical Modelling of the PVT Accuracy

• Positioning Service Availability MPL:

‒ “Propagation and Users Contributions Excluded” → = ‒ The horizontal and the vertical accuracy at each user grid point (at a given epoch) is computed as:

95% = 2

95% = 2 • UTC Time Determination Service Availability MPL:

‒ “For users at a known location” →

‒ “Propagation and Users Contributions Excluded” → = ‒ The UTC Time Determination Accuracy at each user grid point (at a given epoch) is computed as:

95% = 2 = 2 + = 2 ⁄ 1⁄ +

GSA-GAL-GRC-PFR-A10233 43 GGTO Accuracy and Availability GGTO Determination Accuracy (left) and Availability (right)

For the GGTO Determination Accuracy, a reference product is needed for the GGTO. This normally requires a calibrated receiver.

GSA-GAL-GRC-PFR-A10233 44 Timely publications of NAGUs “[…] time intervals within which Galileo NAGUs are published, before any planned event or after any unplanned event.”

GSA-GAL-GRC-PFR-A10233 45 MPLs for OS - Summary Five main groups of MPLs can be identified from the GAL OS SDD

• Galileo SIS Ranging • Galileo SIS UTC Time • MPL of the • MPL of the GGTO • Timely Publications al MPL Accuracy for Dissemination Acc. Availability of the Determination of NAGUs (Table 21) any SV (Table 9) MPL (Table 11) PDOP (Table 15) Accuracy (Table 19) • Galileo SIS Ranging • Galileo SIS UTC • MPL of the • MPL of the GGTO Sign Timing rability

Accuracy MPL over Frequency Availability of the Determination cations All SVs (Table 10) Dissemination Acc. Positioning Service Availability (Table • MPL of the Per-Slot MPL (Table 12) (AUL, WUL) (Tables 20) Availability (Table • MPL of the Positioning 16, 17) 13) Availability of the Galileo OS UTC Time

Dissemination Interope Service (Table 14) • MPL of the User Notifi Availability of the UTC Time Determination Service (WUL only) (Table 18)

GSA-GAL-GRC-PFR-A10233 46 What do we need for each MPL? (1/4)

MPL (and Table of the GAL Consolidated Navigation Reference Products User Grid Point/Service SISE Error Model () OS SDD) Message Volume Simulation Galileo SIS Ranging MPL Yes. Yes. Yes, if the numerical Not Needed. Accuracy for any SV (Table The (consolidated) Reference products are derivation is used. This 9) navigation message is needed for SV orbit and approach requires: needed to retrieve clock (including BGDs). • A suitable grid of broadcast values for SV These need to be possible user locations; orbits, clocks, BGDs, SIS complemented by: and Health Status, and AOE. • Antenna offset • The identification of information; and the User Grid Points in • Attitude law (also valid view of the SV. during SV eclipse Not needed, if the periods). analytical derivation is used. Galileo SIS Ranging As above. As above. As above. As above. Accuracy MPL over All SVs (Table 10)

GSA-GAL-GRC-PFR-A10233 47 What do we need for each MPL? (2/4)

MPL (and Table of the GAL Consolidated Navigation Reference Products User Grid Point/Service SISE Error Model () OS SDD) Message Volume Simulation Galileo SIS UTC Time Yes. Yes. Not Needed. Not Needed. Dissemination Acc. MPL It is needed to retrieve the A reference product is (Table 11) broadcast (GST-UTC) offset. needed for the (GST-UTC) offset. This normally requires: • A calibrated receiver; • A connection to a Timing Laboratory; and • BIPM information. Galileo SIS UTC Frequency As above. As above. As above. As above. Dissemination Acc. MPL (Table 12) MPL of the Per-Slot Yes. Not Needed. Not Needed. Not Needed. Availability (Table 13) It is needed to retrieve the SIS Health Status and the AOE of each SV.

GSA-GAL-GRC-PFR-A10233 48 What do we need for each MPL? (3/4)

MPL (and Table of the GAL Consolidated Navigation Reference Products User Grid Point/Service SISE Error Model () OS SDD) Message Volume Simulation MPL of the Availability of Yes. Not Needed. Yes. Not Needed. the Galileo OS UTC Time It is needed to retrieve the Dissemination Service broadcast (GST-UTC) offset (Table 14) MPL of the Availability of Yes. Not Needed. Yes. Not Needed. the PDOP (Table 15) It is needed to retrieve the SIS Health Status and the AOE of each SV. MPL of the Availability of Yes. Not Needed. Yes. Yes. the Positioning Service It is needed to retrieve the (AUL, WUL) (Tables 16, 17) SIS Health Status and the AOE of each SV. MPL of the Availability of Yes. Not Needed. Yes. Yes. the UTC Time It is needed to retrieve the A model for the std. dev. of Determination Service SIS Health Status and the the UTC Time Diss. Error (WUL only) (Table 18) AOE of each SV. () is also needed.

GSA-GAL-GRC-PFR-A10233 49 What do we need for each MPL? (4/4)

MPL (and Table of the GAL Consolidated Navigation Reference Products User Grid Point/Service SISE Error Model () OS SDD) Message Volume Simulation MPL of the GGTO Yes. Yes. Not Needed. Not Needed. Determination Accuracy It is needed to retrieve the A reference product is (Table 19) broadcast GGTO, the SIS needed for the GGTO. This Health Status and the AOE normally requires a of each SV. calibrated receiver. MPL of the GGTO Yes. Not Needed. Yes. Not Needed. Determination Availability It is needed to retrieve the (Table 20) broadcast GGTO, the SIS Health Status and the AOE of each SV. Timely Publications of Yes. Not Needed. Not Needed. Not Needed. NAGUs (Table 21) It is needed to retrieve the SIS Health Status and the AOE of each SV.

GSA-GAL-GRC-PFR-A10233 50 Linking space to user needs

How to get in touch: www.GSA.europa.eu

EGNOS-portal.eu GSC-europa.eu G UseGalileo.eu

51 Performance monitoring and assessment needs Galileo Workshop 2021: All you need to know about Europe’s GNSS performance Lennard HUISMAN, GSA-GRC

03.03.2021 – Noordwijk (NL) 52 What do we need for each MPL?

MPL (and Table of the GAL OS SDD) Table Consolidated Reference Products User Grid Point/Service SISE Error Model in SDD Navigation Volume Simulation () Message Galileo SIS Ranging MPL Accuracy for any SV 9 Yes. Yes. (Orbit, Clock, BGD, Antenna Yes. Not Needed. offset). Galileo SIS Ranging Accuracy MPL over All SVs 10 Yes. Yes. (Orbit, Clock, BGD, Antenna Yes. Not Needed. offset). Galileo SIS UTC Time Dissemination Acc. MPL 11 Yes. Yes. (GST-UTC offset). Not Needed. Not Needed. Galileo SIS UTC Frequency Dissemination Acc. MPL 12 Yes. Yes. (GST-UTC offset). Not Needed. Not Needed. MPL of the Per-Slot Availability 13 Yes. Not Needed. Not Needed. Not Needed. MPL of the Availability of the Galileo OS UTC Time Dissemination Service 14 Yes. Not Needed. Yes. Not Needed. MPL of the Availability of the PDOP 15 Yes. Not Needed. Yes. Not Needed. MPL of the Availability of the Positioning Service (AUL, WUL) 16,17 Yes. Not Needed. Yes. Yes.

MPL of the Availability of the UTC Time Determination Service (WUL only) 18 Yes. Not Needed. Yes. Yes. (and). MPL of the GGTO Determination Accuracy 19 Yes. Yes. (GGTO). Not Needed. Not Needed. MPL of the GGTO Determination Availability 20 Yes. Not Needed. Yes. Not Needed.

Timely Publications of NAGUs 21 Yes. Not Needed. Not Needed. Not Needed. GSA-GAL-GRC-PFR-A10233 53 Performance monitoring using publicly available data

• Performance monitoring requires the following data and products: ‒ Consolidated navigation messages ‒ Reference orbits, clocks, BGDs ‒ Antenna offset information ‒ Reference station observation data ‒ Reference station coordinates ‒ Calibrated timing receivers ‒ NAGU monitoring

GSA-GAL-GRC-PFR-A10233 54 Performance monitoring using publicly available data

• Performance monitoring requires the following data and products: ‒ Consolidated navigation messages Publicly available in ‒ Reference orbits, clocks, BGDs standardized data formats ‒ Antenna offset information ‒ Reference station observation data ‒ Reference station coordinates ‒ Calibrated timing receivers ‒ NAGU monitoring

GSA-GAL-GRC-PFR-A10233 55 International GNSS Service (IGS)

• Voluntary federation • Around 350 self-funding agencies, universities, and research institutions in more than 100 countries • Free and open access to precise products and data (real-time and file format) ‒ Orbits, clocks, ionosphere, troposphere, system biases ‒ Tracking data for over 500 GNSS stations, ITRS realization • https://www.igs.org/

GSA-GAL-GRC-PFR-A10233 56 Product data formats

Product File formats (FTP/HTTPS) 1 Streaming format (NTRIP) 1 Consolidated navigation messages RINEX Navigation 2 RTCM SC-104 Ephemeris (BCEP) 3 Reference satellite orbits SP3 2 RTCM SC-104 State Space Representation (SSR) 3 IGS SSR 2 Reference satellite clocks SP3 2 RTCM SC-104 SSR 3 Clock RINEX 2 IGS SSR 2 Reference Broadcast Group Delays Bias-SINEX 2 RTCM SC-104 SSR 3 IGS SSR 2 Antenna offset information ANTEX 2 Reference station observation data RINEX Observation 2 RTCM SC-104 Multi System Messages (MSM) 3 Reference station coordinates SINEX 2 RTCM SC-104 MSM 3

1) Protocols used at IGS data centers (https://www.igs.org/products-access/ and https://www.igs.org/wg/real-time/) 2) IGS formats (https://www.igs.org/formats-and-standards/)

3) RTCM SC-104 format (https://www.rtcm.org/)

GSA-GAL-GRC-PFR-A10233 57 What do we need for each MPL?

Timely Publications of NAGUs 21 Yes. Not Needed. Not Needed. Not Needed. GSA-GAL-GRC-PFR-A10233 58 Performance monitoring using only consolidated navigation message

Timely Publications of NAGUs 21 Yes. Not Needed. Not Needed. Not Needed. GSA-GAL-GRC-PFR-A10233 59 Consolidated navigation messages (.RNX)

• GNSS receivers report navigation messages in their field of view • For a global monitoring unique messages need to be combined  Consolidated navigation message • Consolidated navigation messages are available through: ‒ IGS global data centers (RINEX format) ‒ IGS real-time products caster (RTCM SC-104) (or RTCM 10403.3?) • Quality check is important ‒ No standard for generation (majority voting, first to arrive, …) ‒ Receiver manufacturers’ implementation of generation of navigation files (especially GAL and BDS)

GSA-GAL-GRC-PFR-A10233 60 Performance monitoring using only navigation message

3.04 NAVIGATION DATA MIXED RINEX VERSION / TYPE MergeMNfile.tcl IGS 20210301 091018 GMT PGM / RUN BY / DATE (Merged) broadcast gfzrnx-1.13-7761 FILE MERGE 20210228 000756 UTC COMMENT ephemeris GAL 4.7500e+01 1.0160e-01 -1.5260e-04 0.0000e+00 IONOSPHERIC CORR GAGP 0.5355104804E-08 0.346389584E-13 0 2147 TIME SYSTEM CORR MPL of the Per-Slot Availability X GAUT 0.0000000000E+00 0.000000000E+00 518400 2146 TIME SYSTEM CORR END OF HEADER MPL of the Availability of the X E02 2021 02 27 06 00 00 2.013733028434E-04 2.700062395888E-12 0.000000000000E+00 Galileo OS UTC Time 4.000000000000E+00-6.528125000000E+01 3.355854070506E-09 1.598438045406E+00 Dissemination Service -3.097578883171E-06 4.342391621321E-04 4.526227712631E-06 5.440595748901E+03

MPL of the Availability of the X 5.400000000000E+05 8.195638656616E-08 2.162865856159E+00-3.725290298462E-08 PDOP 9.786830298480E-01 2.537812500000E+02 3.461314792512E-01-5.795241395066E-09 -5.589518540169E-10 5.170000000000E+02 2.146000000000E+03 MPL of the GGTO Determination X Availability 3.120000000000E+00 0.000000000000E+00-1.164153218269E-09-1.862645149231E-09 5.406850000000E+05

GSA-GAL-GRC-PFR-A10233 61 Performance monitoring using reference products (orbit, clock, BGD, ANTEX)

MPL (and Table of the GAL OS SDD) Table Consolidated Reference Products User Grid Point/Service SISE Error Model in SDD Navigation Volume Simulation () Message Galileo SIS Ranging MPL Accuracy for any SV 9 Yes. Yes. (Orbit, Clock, BGD, Antenna Yes. Not Needed. offset). Galileo SIS Ranging Accuracy MPL over All SVs 10 Yes. Yes. (Orbit, Clock, BGD, Antenna Yes. Not Needed. offset). Galileo SIS UTC Time Dissemination Acc. MPL 11 Yes. Yes. (GST-UTC offset). Not Needed. Not Needed. Galileo SIS UTC Frequency Dissemination Acc. MPL 12 Yes. Yes. (GST-UTC offset). Not Needed. Not Needed. MPL of the Per-Slot Availability 13 Yes. Not Needed. Not needed. Not Needed. MPL of the Availability of the Galileo OS UTC Time Dissemination Service 14 Yes. Not Needed. Yes. Not Needed. MPL of the Availability of the PDOP 15 Yes. Not Needed. Yes. Not Needed. MPL of the Availability of the Positioning Service (AUL, WUL) 16,17 Yes. Not Needed. Yes. Yes.

Timely Publications of NAGUs 21 Yes. Not Needed. Not Needed. Not Needed. GSA-GAL-GRC-PFR-A10233 62 Performance monitoring using reference products (orbit, clock, BGD, ANTEX)

Transform to Compute orbit Apply antenna radial, along, difference Precise satellite orbit offsets across track (ECEF) (.SP3) difference

Antenna offsets (.ATX) Compute global average Consolidated SISE value Navigation Messages (.RNX)

Signal code biases Apply signal Compute clock (.BIA) code bias difference

Precise satellite clock (.CLK)

GSA-GAL-GRC-PFR-A10233 IGS SSR orbits, clocks and biases

• Tow types available ‒ SSRA (gives position of the satellites Antenna Phase Centre (,)) ‒ SSRC (gives position of the satellites Centre of Mass (,)) • Corrections defined relative to INAV message with specific IOD (reference product is independent from service): Δ() = ,() − , . Δ() = ,() − , . • Pitfall: IOD in SSR uses 8LSB of the 10 bit Galileo IOD, a sanity check is required to find the matching INAV(IOD) message

• SSR contains observable specific code biases ( , ) which should be consistent with the provided clock correction

GSA-GAL-GRC-PFR-A10233 64 Performance monitoring using reference products (real-time streams) Precise satellite orbit APC Transform to Compute orbit Apply antenna radial, along, difference Precise satellite orbit offsets across track Reconstruct CoM (ECEF) precise orbit difference

Antenna offsets (.ATX) Compute global average SSRA or SSRC BCEP stream SISE value stream Consolidated Navigation Messages

Apply signal Compute clock Signal code biases Reconstruct code bias difference precise clock

Precise satellite clock

GSA-GAL-GRC-PFR-A10233 Tools for navigation messages and reference products

• Navigation file QC and merge: ‒ Gnut Anubis (https://gnutsoftware.com/software/anubis) ‒ GFZRNX (https://dataservices.gfz-potsdam.de/panmetaworks/showshort.php?id=escidoc:1577894) • Reading files and streams, compute satellite positions, clock offset, biases, health status, receiver positioning, …. ‒ Several open source tools available that contain library functionality ‒ RTKLIB (http://www.rtklib.com/) * ‒ BKG NTRIP Client (BNC) (https://igs.bkg.bund.de/ntrip/download) * ‒ G-Nut Anubis (https://gnutsoftware.com/software/anubis) ‒ goGPS (https://gogps-project.github.io/) ‒ … *) Supports real-time streams

GSA-GAL-GRC-PFR-A10233 66 Performance monitoring using reference products (orbit, clock, BGD, ANTEX)

MPL (and Table of the GAL OS SDD) Table Consolidated Reference Products User Grid Point/Service SISE Error Model in SDD Navigation Volume Simulation () Message Galileo SIS Ranging MPL Accuracy for any SV 9 Yes. Yes. (Orbit, Clock, BGD, Antenna Yes. Not Needed. offset). Galileo SIS Ranging Accuracy MPL over All SVs 10 Yes. Yes. (Orbit, Clock, BGD, Antenna Yes. Not Needed. offset). Galileo SIS UTC Time Dissemination Acc. MPL 11 Yes. Yes. (GST-UTC offset). Not Needed. Not Needed. Galileo SIS UTC Frequency Dissemination Acc. MPL 12 Yes. Yes. (GST-UTC offset). Not Needed. Not Needed. MPL of the Per-Slot Availability 13 Yes. Not Needed. Not needed. Not Needed. MPL of the Availability of the Galileo OS UTC Time Dissemination Service 14 Yes. Not Needed. Yes. Not Needed. MPL of the Availability of the PDOP 15 Yes. Not Needed. Yes. Not Needed. MPL of the Availability of the Positioning Service (AUL, WUL) 16,17 Yes. Not Needed. Yes. Yes.

Timely Publications of NAGUs 21 Yes. Not Needed. Not Needed. Not Needed. GSA-GAL-GRC-PFR-A10233 67 Performance monitoring using public available data

GSA-GAL-GRC-PFR-A10233 68 Linking space to user needs

How to get in touch: www.GSA.europa.eu

EGNOS-portal.eu GSC-europa.eu G UseGalileo.eu

69 Reference products generation Galileo Workshop 2021: All you need to know about Europe’s GNSS performance Andrea NARDO, GSA-GRC 03.03.2021 – Noordwijk (NL) 70 Creating reference products

• Example: 24-h campaign ‒ Estimate orbit ‒ Clocks ‒ Differential code biases • Target accuracy: ‒ Orbit: 5-10 cm 3D rms ‒ Clock: 0.1-0.2 nsec (std) ‒ DCB (P1-P2,E1-E5a): few cm • Global network of geodetic grade receivers (~100 receivers) ‒ Rinex obs & nav

GSA-GAL-GRC-PFR-A10233 71 Creating reference products: orbit

Code-based Receiver • Linearized problem clock synchronization • Requires an initial orbit RNXO Cycle slips / outliers • Variational EOP equations have to Create double WL/NL be integrated in differences Ambiguity fixing RNXN order to compute the state transition ANTEX/Satellite matrix Solve normal metadata equation • The state transition SUN/MOON matrix links the Trajectory and initial state (position variational equations GRAVITY/TIDES and velocity) to any adaptation Initial state, solar radiation pressure parameters, observation at any Station station coordinates, zenith epoch information troposphere delay and its gradient (ambiguities)

GSA-GAL-GRC-PFR-A10233 72 Creating reference products: orbit modelling 1/2

• Initial orbit derived from the consolidated navigation message (24h batch) • Initial EOPs derived from IERS Bulletin (gpsrapid daily) • Integrate equation of motion and variational equations

‒ Gravity: EGM2008, 8th degree/order

‒ Sun/Moon perturbation: JPL DE405 ephemeris

‒ Solid Earth tides and Pole Tides (IERS2010), Ocean Tides, Ocean Tidal Loading and Geocenter Correction (FES2004)

‒ Runge-Kutta / Adams-Bashfort-Moulton

‒ Orbit Polynomial representation: 10 degree, 1h validity interval

‒ Variational Equations representation: 12 degree, 6h validity interval • A priori Solar Radiation Pressure Model (box wing) / Antenna Thrust

‒ In combination with Empirical Models (E.G. ECOM,ECOM2) to estimate Solar Radiation Pressure parameters (SRP) • Stochastic (velocity) pulses used to absorb remaining mismodelled effects • Several iterations are needed (3), depending on the quality of the initial orbit.

‒ Also, number and type of SRP parameters are critical for convergence (reduced parametrization for the first iteration)

GSA-GAL-GRC-PFR-A10233 73 Creating reference products: orbit modelling 2/2

• Ionosphere: ionosphere free code and phase combination

‒ Double difference (no receiver/satellite clock estimation, double differenced ambiguity are integer) • A priori Zenith Troposphere Delay (ZTD)

‒ A priori (dry part, E. G. based on GPT) • Receiver / Transmitter Phase Center Variation (PCV) and Offset (PCO) • Estimated parameters:

‒ Receiver coordinates (a subset of them is fixed/constrained to a priori values to define the reference frame)

‒ EOPs (a subset of them is fixed/constrained to a priori values)

‒ Wet part of the Zenith Troposphere Delay and its gradient

‒ Satellites initial states

‒ Solar Radiation Pressure (D - sun direction, Y - Satellite Panel axis, X – normal to D and Y), constant and periodic terms

‒ Stochastic pulses, (1 at noon, per satellite)

‒ Nuisance parameters: float ambiguities (can be fixed to integer values to improve the precision of the final estimates and/or reduce the size of the normal equation matrix that has to be inverted)

GSA-GAL-GRC-PFR-A10233 74 SINEX files / EOP files

• SINEX V2.02 (2006) includes ‒ Receiver position and velocity ‒ Variance-Covariance (VCV) matrix ‒ A priori constraints ‒ Station metadata ‒ Used for reference frame monitoring and geodynamics (velocity field and strain rate computation) • More information: https://www.iers.org/IERS/EN/Organization/AnalysisCoordinator/SinexFormat/sinex.html • ITRF14 (latest realization of the International Terrestrial Reference Frame): https://itrf.ign.fr/ITRF_solutions/2014/ITRF2014_files.php • Earth Orientation information (ftp://ftp.iers.org/products/eop/rapid/daily/)

GSA-GAL-GRC-PFR-A10233 75 Satellite Metadata

• GSA provides updates for the Galileo satellites metadata (yaw steering law, geometry, antenna and SLR offsets, check: ‒ https://www.gsc-europa.eu/support-to-developers/galileo-satellite-metadata ‒ Other GNSS PCO/PCV can be found in the IGS antex: ‒ https://files.igscb.org/pub/station/general/igs14.atx ‒ BOX-WING fortran implementation and satellite dimensions and optical property can be found at: ‒ http://acc.igs.org/repro3/repro3.html • QZSS metadata published by JAXA ‒ https://qzss.go.jp/en/technical/qzssinfo/index.html

GSA-GAL-GRC-PFR-A10233 76 RINEX (Receiver Independent Exchange format)

• ASCII files: observations (O), Navigation (N), Meteo (M) ‒ RINEX V1, 5th International Geodetic Symposium on Satellite Positioning, Las Cruces, 1989 • RINEX V2, 2nd International Symposium on Precise Positioning with the Global Positioning System, Ottawa, 1990 ‒ V2.10, GPS and GLONASS ‒ V2.11, GPS, GLONASS, Galileo obs, met and nav. Support for C2, L2C/L5 and Galileo codes • RINEX V3, ‒ V3.01, GPS, GLONASS, Galileo, BeiDou, QZSS and SBAS. Significant change of the data record ‒ V3.02, GLONASS Code-phase bias in the header, changed file naming convention ‒ V3.04, Support for IRNSS, GLONASS CDMA, BeiDou III and QZSS II ‒ V3.05, released in December 2020, full support for BeiDou II and BeiDou III, adds missing flags and values to the GLONASS navigation message ‒ More details: (https://www.igs.org/formats-and-standards/#)

GSA-GAL-GRC-PFR-A10233 77 RINEX Public sources – FTP servers

• Data can be retrieved from global, regional and local centre • The data availability of these three different types of data centre may differ (e.g. not all the stations available in the regional centre are in the global data centres) • FTP servers Global Centres: ‒ Crustal Dynamic Data Information System (CDDIS) (IGS) ‒ Institut Geographique National (IGN) (IGS) • FTP servers regional Centres ‒ Bundesamt für Kartographie und Geodäsie (BKG) (IGS) • FTP local data centres: ‒ The Geodetic Observatory Pecny (European Permanent Network, EPN) ‒ Usually 30-seconds observation rinex files (1-seconds also available) • For an overview: https://epncb.eu/_networkdata/data_access/dailyandhourly/datacentres.php

GSA-GAL-GRC-PFR-A10233 78 RNX2CRX, CRX2RNX: compression tools

• RINEX 2.11 addendum (https://files.igs.org/pub/data/format/Addendum- rinex211.pdf) encourages the use of the compression program Gzip to reduce the file size (binary) ‒ Addition compression can be achieved on ascii files by using a compression scheme proposed by Y. Hatanaka ‒ RNX2CRX implements Hatanaka’s compression algorithm ‒ CRX2RNX decompresses previously Hatanaka compressed files ‒ The suggested compression scheme is: .rnx => (RNX2CRX, ascii) => (Gzip, binary) • More info: https://terras.gsi.go.jp/ja/crx2rnx.html

GSA-GAL-GRC-PFR-A10233 79 GFZRNX, TEQC: editing tools

• Split, merge, concatenation of rinex files • Rinex Header editing (TEQC, GFZRNX) • Observation removal (observation type, system) (TEQC, GFZRNX) • Basic statistics (TEQC, GFZRNX) • Conversion between rinex V2 and rinex V3 (and viceversa) (GFZRNX) ‒ File Naming ‒ Data format • TEQC: rinex V2 • GFZRNX: rinex V2 and rinex V3

GSA-GAL-GRC-PFR-A10233 80 Creating reference products: clock

Receiver and satellites clock corrections (5 minutes), Zenith troposphere delays Code-based Receiver Cycle slips / PPP-like clock synchronization outliers and its gradient, estimation based (ambiguities) on ionosphere- RNXO free combination

RNXN

PRECISE ORBIT

Station information EOP

ANTEX/satellite Delta-phase clock densification (30 metadata seconds) TIDES

Delta-phase densification is used to avoid to solve for the ambiguities GSA-GAL-GRC-PFR-A10233 81 Creating reference products: clock estimation

• Based on Undifferenced Ionosphere free phase and code observations • Fixed parameters: ‒ Precise Orbit ‒ EOPs ‒ Coordinates • Solve for: ‒ (wet) Zenith Troposphere Delay and gradient ‒ Ionosphere free ambiguities ‒ Receiver/satellites clocks (+zero mean condition or external constraints) • Receiver and Satellite clock corrections modelled as epoch parameters ‒ Large number of unknows (especially for batch estimation) • Correction sampling rate: 300 seconds

GSA-GAL-GRC-PFR-A10233 82 Creating reference products: clock densification

• 300 seconds sampling is not high enough for precise positioning • Time Differenced Ionosphere free phase observations Low rate • Fixed parameters: Densified ‒ Precise Orbit ‒ EOPs

‒ Coordinates dt • Solve for: ‒ Receiver/satellites delta-clocks • Correction sampling rate: 30 seconds

GSA-GAL-GRC-PFR-A10233 t Differential Code Biases estimation

Code smoothing by Code-based Receiver carrier phase clock synchronization outliers

RNXO

PRECISE ORBIT PPP-like estimation based PRECISE SATELLITE on ionosphere CLOCK combination Station information EOP

ANTEX/satellite Receiver and satellites metadata Differential Code Biases (iono ambiguities), Spherical TIDES harmonics coefficients

GSA-GAL-GRC-PFR-A10233 84 Creating reference products: DCBs

• Based on undifferenced code smoothed by phase ionosphere combination ‒ Geometry free combination does not strictly require the use of precise orbits/clocks/eop ‒ However, they are used, especially for the preprocessing and are already available from the orbit and clock estimations • Relation between DCB and BGD:

, , = − 1 − • Orbit and EOPs fixed to the previously estimated values • Vertical Total Electron Content (VTEC) is spatially represented by a thin layer ‒ Slant ionosphere delays are mapped to VTEC at the Ionospheric Pierce Point through a Mapping Function ‒ Spherical harmonics representation (15 deg/order, height 450 Km) ‒ Spherical harmonics coefficients are estimated in the sun-fixed reference frame, to reduce temporal variability ‒ Ionosphere snapshots (1-hour sampling) ‒ Daily values for receiver/satellite DCB

GSA-GAL-GRC-PFR-A10233 85 BERNESE, NAPEOS, GIPSY

• Scientific software for high precision positioning • Orbit determination (state, radiation pressure parameters, stochastic pulses) • Earth Orientation Parameters • Satellite and receiver clock estimation • Ionosphere estimation • Differential positioning and precise point positioning • Differential Code bias Estimation • Phase Centre offset And Variation Estimation • Low Earth Orbiter kinematic and reduced dynamic orbit determination • Laser Ranging • Station velocity estimation (normal equation stacking)

GSA-GAL-GRC-PFR-A10233 86 Linking space to user needs

How to get in touch: www.GSA.europa.eu

EGNOS-portal.eu GSC-europa.eu G UseGalileo.eu

87 Service performance monitoring at the GRC Galileo Workshop 2021: All you need to know about Europe’s GNSS performance Marco PORRETTA, Peter BUIST, GSA-GRC

03.03.2021 – Noordwijk (NL) 88 SIS Ranging Accuracy – Long Term

SDD 1.0 SDD 1.1

GSA-GAL-GRC-PFR-A10233 89 Ranging Accuracy – Any Satellite

GSA-GAL-GRC-PFR-A10233 90 Ranging Accuracy – Constellation Avg.

GSA-GAL-GRC-PFR-A10233 91 Per Slot Availability (Constellation Avg.) Availability is calculated over 12 months, therefore effect of outage in July 2019 is removed from July 2020 onwards

GSA-GAL-GRC-PFR-A10233 92 UTC Time Dissemination Accuracy

January 2020 Handover of the timing chain to PTF-I: UTC(SIS) Accuracy Offset from -10ns to +5ns.

GSA-GAL-GRC-PFR-A10233 93 GST-UTC Dissemination Availability

Service unavailable on 14 December

GSA-GAL-GRC-PFR-A10233 94 Availability of PDOP at AUL

Service unavailable on 14 December

GSA-GAL-GRC-PFR-A10233 95 Avail. of the Positioning Service (AUL)

1st time 100% Service unavailable on 14 December

GSA-GAL-GRC-PFR-A10233 96 Avail. of the Positioning Service (WUL)

1st time 100% Service unavailable on 14 December

GSA-GAL-GRC-PFR-A10233 97 GST-UTC Determination Availability

GST-UTC unavailable on 14 December

GSA-GAL-GRC-PFR-A10233 98 GGTO Determination Accuracy

January 2020 Handover of the timing chain to PTF-I: GGTO(SIS) Accuracy Offset from +10ns to +3ns.

GSA-GAL-GRC-PFR-A10233 99 GGTO Availability GGTO unavailable on 7-8 February and 14-15 February (NAGU 2020002 & NAGU 2020004) GGTO unavailable on 14 December

GSA-GAL-GRC-PFR-A10233 100 Galileo OS Performance

Target OS MPLs Target Value December 2020 December 2020 OS MPLs Value UTC Time  30 ns [95%] 9.79 0.36 0.20 0.22 0.19 0.19 0.21 0.22 0.22 Dissemination [ns] E5a-E1 user 0.28 0.28 0.22 0.23 0.24 0.23 0.18 0.24 UTC Frequency  3E-13 [95%] 1.23E-14 0.23 0.25 0.23 0.20 0.18 0.19 0.24 0.29 Dissemination [adm] Accuracy 0.34 0.31 0.28 0.20 0.17 0.21 0.21 0.19 GGTO Determination  20 ns [95%] 9.61 E5b-E1 user 0.25 0.28 0.19 0.21 0.21 0.22 0.18 0.21 [ns] 0.20 0.21 0.17 0.19 0.20 0.18 0.22 0.28  7m 0.36 0.23 0.28 0.27 0.31 0.38 0.29 0.32 Timing UTC Dissemination  87% 99.22 E1 user 0.26 0.39 0.23 0.30 0.28 0.29 0.28 0.30 UTC Determination [95%] 0.26 0.29 0.23 0.26 0.34 0.27 0.33 0.40  87% 99.22 Accuracy 0.45 0.32 0.41 0.38 0.52 0.62 0.46 0.50

E5a user 0.48 0.55 0.33 0.44 0.47 0.47 0.45 0.52 Availability[%] GGTO Determination  80% 99.38

Accuracy, Any [m] Satellite 0.38 0.50 0.39 0.38 0.53 0.40 0.57 0.57 0.39 0.36 0.34 0.35 0.47 0.56 0.40 0.45 PDOP  6, F/NAV 77% 99.18 E5b user 0.41 0.51 0.28 0.40 0.45 0.43 0.39 0.45 0.34 0.44 0.35 0.35 0.48 0.38 0.52 0.47 PDOP  6, I/NAV  77% 99.18 E5a-E1 user 0.16 Positioning @ AUL, DF  77% 99.18

SIS Ranging E5b-E1 user 0.17  2m Positioning @ AUL, SF  77% 99.21 E1 user 0.23 Positioning [95%] Availability[%] E5a user 0.33 Positioning @ WUL, DF  70% 99.15 Accuracy, Over All Satellites [m] E5b user 0.31 Positioning @ WUL, SF  70% 99.13 E5a- 99.36 E1 GSC Web site >=95% 100 E5b- [%] 99.39

E1 Availability Per- 

bility bility [%] E1 99.39 Planned Timeliness slot 87%  1 day - [day] E5a 99.36 User Interface Availa

NAGU Unplanned Timeliness  3 days 0.58 E5b 99.39 Timeliness [day] 101 L3 satellites

• The ranging performance for December 2020 is analyzed. The investigation uses reference products generated at the GRC. • Both the MPLs for Ranging Availability (87%) and Ranging Accuracy (7m) are met.

GSA-GAL-GRC-PFR-A10233 102 Performance monitoring using reference products (real-time streams) - Example

• Navigation messages

‒ REGINA network (CNES) • Orbit, clock, code biases:

‒ SSRA00CAS0

‒ SSRA00CNE0

‒ SSRA00DLR0 • Tools:

‒ BNC to decode streams

‒ BNC to create consolidated navigation messages (with some modifications)

‒ RTKLIB APIs used for health status, satellite parameters (position, clock, biases)

‒ Additional code for SISE computation, parsing Bias-SINEX and BNC output • Graphite database

• Grafana dashboards

GSA-GAL-GRC-PFR-A10233 103 Performance monitoring using reference products (real-time streams) - Example

• Navigation messages

‒ REGINA network (CNES) • Orbit, clock, code biases:

‒ SSRA00CAS0

‒ SSRA00CNE0

‒ SSRA00DLR0 • Tools:

‒ BNC to decode streams

‒ BNC to create consolidated navigation messages (with some modifications)

‒ RTKLIB APIs used for health status, satellite parameters (position, clock, biases)

‒ Additional code for SISE computation, parsing Bias-SINEX and BNC output • Graphite database

• Grafana dashboards

GSA-GAL-GRC-PFR-A10233 104 Multi-GNSS

• Galileo Performance: Excellent Accuracy!

GSA-GAL-GRC-PFR-A10233 105 Service performance monitoring: session summary Galileo Workshop 2021: All you need to know about Europe’s GNSS performance Peter BUIST, GSA-GRC

03.03.2021 – Noordwijk (NL) 106 Data and products (1/2)

• Satellite health status has to be verified for FNAV and INAV ephemerides using broadcast navigation data consolidated from a global network. • Consolidated navigation message ‒ No standard how to generate ‒ Quality and availability depends on latency ‒ Receiver issues with messages • Important for users to check the status of the navigation messages as required in the Galileo OS ICD and SDD ‒ Healthy Signal-in-Space flags (SHS, DVS, SISA), Age-of-Ephemerides <4 h ‒ The Galileo system utilizes the 3 SiS health flags to protect the user

GSA-GAL-GRC-PFR-A10233 107 Data and products (2/2)

• Reference stations ‒ Recommended is to use a geodetic grade of receiver connected to a geodetic antenna ‒ High quality data and multiple frequencies and signals • Real-time data ‒ provides overview of GNSS status in nominal situations ‒ Unusual events / anomalies might be not reflected properly in the SSR corrections

GSA-GAL-GRC-PFR-A10233 108 Overall conclusion

The GNSS provider operates the system to maintain the SDD, performance may vary within the margins due to operational, maintenance or deployment constraints

For GNSS performance monitoring: • Interpretation of results is key • Good practice is to make use of redundancy ‒ always confirm, when possible, results with other sources

GRC is the European hub for performance monitoring activities

GSA-GAL-GRC-PFR-A10233 109 Linking space to user needs

How to get in touch: www.GSA.europa.eu

EGNOS-portal.eu GSC-europa.eu G UseGalileo.eu

110