GNSS in der Luftfahrt - Plone siteGNSS in der Luftfahrt. Galileo Architektur und Status. 2 1/14/202 0 ... European GNSS Agency •Operations and provision of services is entrusted

T. Pany

Professur für Satellitennavigation (LRT 9.2)

Institut für Raumfahrttechnik und Weltraumnutzung

GNSS in der LuftfahrtGalileo Architektur und Status

21/14/2020 Conference/Workshop/Event 2SatNav 2: GNSS in der Luftfahrt

Inhalt

Bereits besprochen• Galileo-Geschichte, Galileo-Satellit

• SatNav I, GloSatSys VO4• Galileo Dienste und Signale

• SatNav I, GloSatSys VO9

• Systemarchitektur• Konstellation• Bekannte Ausfälle und deren Gründe• Status Performance

• Galileo und autonomes Fahren• High-Accuracy-Service


SystemarchtikturPolitisch, Aufbau, GCS, GMS


Galileo Political Architecture

European Commission•Overall responsibility for the programme, management and implementation of all activities lies within the European Commission•Since 2020: Galileo is handled within the Directorate General for Defense Industry and Space (DEFIS) headed by•T. Breton (Commissioner), T. Pesonen (Director General), Pierre Delsaux(Deputy director general)

European Space Agency•Deployment, design and development of new generations and technical infrastructure is carried out by ESA

European GNSS Agency•Operations and provision of services is entrusted to GSA


DG DEFIS

https://ec.europa.eu/info/sites/info/files/dg-defis-organigramme_en.pdf


Galileo Political Architecture

Source: https://www.slideshare.net/EU_GNSS/gsa-egnos-and-galileo-for-aviation


European GNSS Agency

• European GNSS Agency (formerly European GNSS Supervisory Authority) in Prague

• Responsible for operations and service provision• Oversees key facilities:

• Galileo Security Monitoring Center (GSMC)• European GNSS Service Center (GSC)• Galileo Reference Center (GRC)• Galileo Integrated Logistics Support Center (GILSC)• Galileo Control Centers (GCCs)

• Market analysis• GNSS/Galileo uptake

Source: https://www.gsa.europa.eu


Galileo System Architecture

Source: 2014-springer-galsyst-9789400718296-c2


Galileo Control Segment (GCS)


• Responsible for satellite constellation controland management of satellites

• Provision of telemetry, telecommand and control functions for the whole satellite const.

• Core facilities:• Galileo Control Centers (GCCs)• Telemetry, Tracking & Control (TT&C) stations


Galileo Mission Segment (GMS)


• Responsible for the determination and uplink ofnavigation data messages needed to providenavigation and UTC time transfer services

• Continuous, global monitoring of all Galileo navigation signals and upload of updatednavigation messages

• Core facilities:• Galileo Control Centers (GCCs)• Galileo Up-Link Stations (ULS)• Galileo Sensor Stations (GSS)


Galileo Control Center (GCC)

Source: https://gssc.esa.int/navipedia/index.php/Galileo_Ground_Segment

GCS facilities within GCC:•Spacecraft & Constellation Control Facility, SCCF•Spacecraft & Constellation Planning Facility, SCPF•Flight Dynamics Facility, FDS•Operations Preparation Facility, OPF•Central Monitoring & Control Facility, CMCF•GCS Key Management Facility, GCS KMF•Constellation Simulator, CSIM

GMS facilities within GCC:•Orbit Determination and Synchronization Processing Facitility, OSPF•Message Generation Facility, MGF•Precision Timing Facility, PTF•Ground Assets Control Facility, GACF•Mission Uplink Control Facility, MUCF•Mission Support Facility, MSF•Maintenance and Training Platform, MTPF•GMS Key Management Facility, GMS KMF•Service Product Facility, SPF


Galileo System – Ground Segment -2010

Source: http://www.aiad.it/aiad_res/cms/documents/TELESPAZIOgalileocontrolcenter_eng.pdf


Galileo System – Ground Segment -2018

http://www.esa.int/Applications/Navigation/Galileo_s_ground_control_segment_contracted_for_upgrade


Galileo System Architecture – Add-on

Source: Galileo-At-the-Dawn-of-a-New-Age-of-GNSS-Services-12.19.16

Galileo Control Center Oberpfaffenhofen

Sensor plus Uplink Station


KonstellationDerzeitiger Stand, weitere Beschaffungen


Galileo Launch Status

Source: https://de.slideshare.net/EU_GNSS/status-of-galileo

Overlap with next slide (2018 was Launch 10 = L10)


Galileo Future Launch Status

Chatre, Eric, Benedicto, Javier, "2019 – Galileo Programme Update," Proceedings of the 32nd International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2019), Miami, Florida, September 2019, pp. 650-698.


Galileo Batch 3 Satellites (Launch 2020+)



Galileo Current Constellation (Dec. 2019)

Source: https://www.gsc-europa.eu/system-status/orbital-and-technical-parameters/parameters-definition


Galileo Satellites - Current Status

Source: https://www.gsc-europa.eu/system-status/Constellation-Information, 13.1.2020, 9:55 (UTC)

Wrong orbit

Next clock failure?


Galileo – Known Issues

•Overall 9 clock failures (6 PHM and 3 RAFS) until now (Status mid. 2019)

•The 3 RAFS failures occured on FOC SVs•1 PHM failure occured on an FOC SV•5 PHM failures occured on IOV satellites•3 of the 4 IOVs and 2 of the 26 FOCs are affected•Galileo still fully functional due to redundancy•PHM: issues when (re-)starting the clock related to plasma generation•RAFS: use of non-qualified electronic parts

Clock issues:

•Galileo 5 and 6 deployed in too low, elliptical orbits•Correction maneuvers were carried out, satellites are nearly fully usable for navigation purposes

Eccentrical orbits:

•Complete service outage from 2019-07-11 – 2019-07-17•Inter-related failures during GMS upgrade process

Galileo Outage:


Galileo Satellite Clocks

http://insidegnss.com/wp-content/uploads/2018/04/Galileo-At-the-Dawn-of-a-New-Age-of-GNSS-Services-12.19.16.pdf updated with https://galileognss.eu/orolia-atomic-clock-supplier-for-foc-galileo-satellites/

All clocks manufactured by SpectraTime (an Oroliacompany) being a single source for Galileo and the only non-US supplier of space atomic clocks.

* Clocks for batch 3 are updated versions of batch ½ clocks* Clocks for transition batch are “customer furnished items (i.e. provided by ESA to satellite manufacturer)


• Eccentrical Orbits: Recovery Maneuvers

Galileo – Eccentrical Orbits

Source: https://insidegnss.com/galileo-5-and-6-eccentric-satellites-mission-recovery-and-exploitation-part-i/

• Wrong orbit for GSAT201, GSAT202 due incorrect launch

• Misplaced cooling line near to fuel line in Soyuz launcher

• Gradual recovery of correct orbit• Sats fully functional

• Increased Doppler e.g. used for science experiments

• Adaptation of navigation message scheduling for official use of satswithin periods of orbit representability


Galileo Incident (based on ESA/EC ION2019 presentation)

Context of incident•Upgrades to Galileo infrastructure necessary to change from “initial services” to “final operational capability”

•Feb. 2019 major upgrade of Galileo operational infrastructure started•July 2019 sequential update of GCCs was ongoing with temporary reduced redundancy of control centers

Causes of incident within GCC•Mishandling of temporary equipment •Technical anomaly of equipment related to time keeping•Non-nominal configuration of that equipment

One or two simultaneous appearances of the causes could have been recovered, but not all three of them

Manifestation•Loss of capability to generated navigation message on July 11, 0:50 UTC•Failure search took several days causing a complete reboot of the system resulting in further delays

•Recovery July 17, ~ 22:00 UTC


Galileo Incident


DVS … Data Validity Status, AOD … Age of Data, SDD … Service Definition Document, IOV … In Orbit Validation, FOC … Final Operational Capability, NAGU … Notice Advisory to Galileo Users

Ephe

mer

is a

ccur

acy

0-10

m

11.7. 2:00 12.7. 2:00


Galileo PerformanzBerichte, Genaugikeiten, Verfügbarkeit, Vergleich GPS


Galileo Performanz

• Technisches Monitoring • In-Orbit-Test• Im Auftrag der GSA

• Berichte• Monatliche Bericht der GSA an

• Kommission• ESA• Mitgliedstaaten der europäischen Union

• Diskussion innerhalb von Arbeitsgruppen der Europäischen Kommission

• Werden Anforderungen erreicht?• Definition neuer Anforderungsmerkmale• Vorschläge zur Verbesserung


Galileo Service URA

Source: Galileo-IS-OS-Quarterly-Performance_Report-Q3-2018


Galileo Satellite URA

From GSA report (Dec. 2019)


Galileo Performance

Source: Galileo-IS-OS-Quarterly-Performance_Report-Q3-2018


Galileo Navigation Performance

Definition Committed Target

Mar2019

Apr2019

May2019

Jun2019

Jul2019

Aug2019

Ranging Accuracy

[m]

DF95%

Worst Satellite < 7.0 0.32 0.59 0.57 0.32 0.34 0.27

Constellation Average < 2.0 0.25 0.31 0.21 0.15 0.21 0.15

SF95%

Worst Satellite < 7.0 0.73 0.56 0.59 0.57 0.57 0.50

Constellation Average < 2.0 0.51 0.38 0.36 0.33 0.31 0.31

Availability of DF Ranging [%](Global average) > 87% 100% 100% Not any more a MPL defined in the OS-SDD

Per-Slot Availability [%](monthly, OS, healthy SF/DF) > 87% 99.05% 98.80% 98.82% 98.70% 97.16% 96.98%

UTC Time Dissemination Uncertainty [ns](DF, 95% over last 12onths) < 30 8.4 8.4 8.3 9.0 11.1 13.1

UTC Frequency Dissemination Uncertainty

(DF, 95% over last 12onths)< 3 × 10-13 3.10E-14 3.14E-14 3.07E-14 3.20E-14 3.50E-14 3.90E-14

Availability of UTC Dissemination [%] > 87% 100% 100% 100% 100% 81.70% 100%

GST-GPS Time Offset Uncertainty [ns](95% over last 12onths) < 20 6.5 6.4 6.4 10.4 12.9 13.5

GST-GPS Time Offset Availability [%](over last 12onths) > 80% 97.33% 96.91% 96.65% 97.48% 95.68% 95.68%

Adapted from GSA report (Dec. 2019)


Galileo Navigation Performance

Definition Committed Target

May2019

June2019

Jul2019

Aug2019

Availability of F/NAV Global PDOP ≤ 6 ≥ 77% 99.58% 99.77% 81.27% 99.71%

Availability of I/NAV Global PDOP ≤ 6 ≥ 77% 99.74% 99.91% 81.37% 99.81%

Availability of Positioningat AUL

95% HPE ≤ 7.5m95% VPE ≤ 15m

Dual Frequency ≥ 77% 99.95% 99.96% 81.53% 99.96%

Single Frequency ≥ 77% 99.90% 99.94% 81.51% 99.94%

Availability of Positioningat WUL

95% HPE ≤ 7.5m95% VPE ≤ 15m

Dual Frequency ≥ 70% 99.69% 99.59% 80.76% 99.71%

Single Frequency ≥ 70% 99.42% 99.44% 80.69% 99.59%

Availability of UTC Determination

(Better than 31 ns, 95% over the month)≥ 87% 100% 100% 81.70% 100 %

Adapted from GSA report (Dec. 2019) AUL … average user location, WUL … worst user location


3.73

4.93

3.38 3.28 3.29

1

0

1

2

3

4

5

6

7

8

Sep-18 Oct-18 Nov-18 Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19

Days

bef

ore

the

even

ts st

arts

NAGU Publication Time - Planned events

Galileo Announcement of Events

0.65

2.56

0.27 0.34 0.45 0.220.81 0.92

1.77

0.37

3

0

1

2

3

4

5

6

7

8

9

Sep-18 Oct-18 Nov-18 Dec-18 Jan-19 Feb-19 Mar-19 Apr-19 May-19 Jun-19 Jul-19 Aug-19

Days

aft

er th

e ev

ents

star

ts

NAGU Publication Time - Unplanned events

All events announced “in time”!

Adapted from GSA report (Dec. 2019)


Galileo-GPS Comparison

• Accuracy (URA, 95 %), monthly average over all satellites (2018):

• Galileo: 0.24 m – 0.5 m• GPS: 1.22 m – 1.35 m

• Time between uplinks:• Galileo: 89.95 % of uplink separations less than 20 min.• GPS: 83.8 % of uplinks less than 24 hrs

• Source: Joint Research Center in contract to GSA (Dec. 2019)


Galileo HAS + G2GGenauigkeit und Integrität durch Vernetzung der Satelliten?


Hintergrund

• Autonomes Fahren ist wie Luftfahrteine sicherheitskritische Anwendung

• Sicherheitsanforderungen für autonomesFahren sind Gegenstand aktueller Diskussionund dürften über jenen von den Zivilluftfahrtliegen (höhere Anzahl an Nutzern)

• Navigationsfähigkeit ist für beide Anwendungen eine Grundvoraussetzung

• Konzepte aus der Luftfahrt (Integrität, ..)können entsprechend übertragen werden

• Beim autonomen Fahren finden aus historischen Gründen vielfach modernere Konzepte der Navigation Einsatz (GNSS: RTK/PPP, optische Verfahren, Radar, KI, …)


Galileo HAS for Autonmous Vehicles

• High Accuracy Service• +/- 20 cm accuracy through PPP corrections

• Support of innovative applications• Autonomous vehicles

• Online System• All data computed in real-time, uplinked and broadcast from so-called connected Galileo satellites

• Data broadcast on Galileo E6 frequency• Orbits, clocks, code biases at high rate (5 – 10 s)• Phase biases at low refreshment rate (30 s – 120 s)• Data support also for GPS measurements carried out by the user (in addition to Galileo

measurements)

• Mean time to retrieve data to allow PPP computation:• Highway conditions (66 % of Galileo sats in view): 7-8 s• Urban conditions (2 Galileo sats in view): 10 – 30 s

• Status:• 2019: CS demo for system connectivity (only dummy data transmitted)• 2019: ITT published and KOM in 2nd half of 2019, draft HAS ICD published in Feb. 2019• 2020/21: engineering work ongoing


Galileo HAS – Connected Satellites

Source: Munich Satellite Navigation Summit 2018 Archive, Session 3, Galileo High Accuracy Service, Ignacio FernandézHernández, European Commission

System integrity achieved through connectivity


Galileo HAS – Comparison to other Services

Source: Munich Satellite Navigation Summit 2018 Archive, Session 3, Galileo High Accuracy Service, Ignacio FernandézHernández, European Commission


Galileo 2nd Generation



Galileo 2nd Generation

• Continuous development of Galileo (G2G) decided by EU and ESA in 2013

• Allocated budget approx. 7 Bill. EUR

• Phase A (concept phase) completed• Three different evolution scenarios analyzed

• From light-weight to major changes

• Consideration of new signals, higher power, inter satellite links

• To improve: accuracy, time-to-first fix, robustness against spoofing/jamming

• New services: Advanced timing, Space service volume, emergency warning service, improved search-and-rescue, ionospheric prediction service, ARAIM

• G2G currently in phase B0 (requirements consolidated)

• Transition Batch Satellites currently under procurement• To start testing of new technologies• Cf. Navigation Test Satellite (NTS-3) for GPS

• https://forum.nasaspaceflight.com/index.php?topic=38903.0

• Currently threes bidders: Thales, OHB, Airbus • Two will be selected to build each two satellites (=total of 4)

• Transition Ground Segment• Phase B: ongoing• Phase C/D: procurement starting in 2020

https://forum.nasaspaceflight.com/index.php?topic=38903.0


Challenges of a New Generation



Galileo 2nd Generation, Tech. Enablers

2020 around 340M€ (150+ contracts) in GNSS R&D, Chatre et al., 2020.


FragenAuswahl möglicher Prüfungsfragen


Fragen inkl. Punkte

• Wie unterscheidet sich Galileo HAS vom Galileo Open Service. Nennen und beschreiben sie zwei wesentliche Merkmale? (6)

• Hinweis: Konnektivität/Uplinkrate, Genauigkeit

• Welche drei Arten von Performanz-relevanten Vorfällen gab es bei Galileo? Beschreiben Sie sie und geben Sie an, inwiefern jene für eine Nutzung von Galileo in der Zivilluftfahrt relevant sind. (6)

• Welche Rolle haben die europäische Kommission, die ESA und die GSA bei Galileo? (3)

• Erläutern sie die Begriffe Transition Batch und G2G und welche technologischen Zielsetzungen damit erreicht werden sollen (4)

• Welche Schranke wird für den horizontalen Positionierungsfehler angenommen, damit die Verfügbarkeit einer Zweifrequenz-Galileo-Positionierung als gegeben angesehen wird? Welche Zielvorgabe für die prozentuale zeitliche Verfügbarkeit an der dafür ungünstigsten Nutzerposition wird gesetzt (Juni 2019)? (2)

Documents

GNSS in der Luftfahrt - Plone siteGNSS in der Luftfahrt. Galileo Architektur und Status. 2 1/14/202 0 ... European GNSS Agency •Operations and provision of services is entrusted