Galileo System and Signal Evolution

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1 Galileo System and Signal Evolution Stefan Wallner GNSS/Galileo Evolutions Programme ITSNT, 15/11/2017

2 HOW TO DESIGN A GNSS SYSTEM FOR THE YEAR /11/2017 Slide 2

3 Navigation Exponential Evolution ~4000 Years Ago 525 Years Ago 60 Years Ago 15 Years Ago 10 Years Ago <10 Years Ago 15/11/2017 Slide 3

4 PNT Short Term ESA UNCLASSIFIED For Official Use 15/11/2017 Slide 4

Flexibility / Time-to-market Rollout of GNSS Signals and Services: 15 year average Other technologies enabling position can change faster Seeking reduction of

5 Flexibility / Time-to-market Rollout of GNSS Signals and Services: 15 year average Other technologies enabling position can change faster Seeking reduction of time-tomarket to 6 months-1year Decoupling SIS-ICD change from replenishment Simulation based on past real data for GPS and planned future launches 15/11/2017 Slide 5

6 Designing PNT Systems for 2040 How can we forecast the breakthroughs of millions of bright engineers in the next 2 decades? GNSS, the Robust Backbone of PNT GNSS Flexibility for adaptation to future Added Value services 15/11/2017 Slide 6

7 GALILEO SYSTEM EVOLUTION 15/11/2017 Slide 7

8 The G2G Challenge 15/11/2017 Slide 8

The G2G Options and Downselection Several G2G Mission Evolutions Scenarios have been identified by EC in consultation with all relevant actors (Member States, ESA,

9 The G2G Options and Downselection Several G2G Mission Evolutions Scenarios have been identified by EC in consultation with all relevant actors (Member States, ESA, GSA - providing the user needs ) Corresponding System Evolution Options have been derived by ESA during Phase A for further consolidation in Phase B0 15/11/2017 Slide 9

10 Galileo System Evolution Drivers ESA is in charge of developing system evolution options corresponding to each of the identified mission evolution scenarios Main System Evolution Drivers feeding the mission scenarios: 1. Ensuring service sustainability: constellation replenishment 2. Improving navigation and timing performance 3. Increasing robustness at system and service level 4. Improving service in challenging environments 5. Reducing time-to-market 6. Supporting Safety of Life services (SBAS and ARAIM) 7. Contributing to Space Service Volume 8. Enhancing SAR (Second Generation Beacon compatibility, Return link latency reduction) 9. Optimising system operability 10. Reducing lifecycle cost 15/11/2017 Slide 10

Galileo System Evolution Technology Options for Building Blocks 1.

are being developed under the EU Horizon 20

All G2G System/Segment studies and techno developments are being managed by ESA

Introduction of the techno developments in the Galileo system architecture cannot be

Most relevant techno developments for Galileo evolution a) Electric Propulsion

constellation Increase space segment capabilities while maintaining launch costs b)

System/service robustness Improved accuracy Enhanced data dissemination capability

11 Galileo System Evolution Technology Options for Building Blocks 1. Necessary techno developments in support of the different System Evolution Scenarios are being developed under the EU Horizon 2020 (H2020) Programme. 2. All G2G System/Segment studies and techno developments are being managed by ESA (through corresponding Delegation Agreement) 3. Introduction of the techno developments in the Galileo system architecture cannot be confirmed at this stage 4. Most relevant techno developments for Galileo evolution a) Electric Propulsion Providing improved flexibility and cost efficiency when replenishing the Galileo constellation Increase space segment capabilities while maintaining launch costs b) Inter Satellite Links Serves multiplicity of evolution objectives incl. System/service robustness Improved accuracy Enhanced data dissemination capability c) Payload capabilities Improved clock technology (mphm, RRAFS, ONCLE) Direct L-Band Signal Generation for improved flexibility Enhanced Power Amplifier technology d) Enhanced/New Services New Signals to answer evolving user needs Support to Space Service Volume Increase Robustness and Operational Capabilities 15/11/2017 Slide 11

12 GALILEO EVOLUTION SIGNAL EVOLUTION 15/11/2017 Slide 12

13 Open Service Signal in Space Evolution Identified Evolution Objectives Open Service Signal in Space Evolution needs to be capable to respond to agile and fast developing user market Signal in Space Flexibility for Open Service is important key capability in G2G System (Space and Ground Segment) Major trends/needs identified for the future relevant for SIS Low-end receivers (IoT, snapshot receivers, ) Additional and improved data dissemination capability for the provision of additional added value added data to users enabling new services Enhanced robustness to counteract emerging threats (interference, jamming, spoofing) Multi-sensor integration At G2G System level 3 possible directions are studied Low complexity, fast acquisition capability for future low end devices Fast TTFFD, higher demodulation sensitivity, flexibility to introduce new service data Improved authentication at range level 15/11/2017 Slide 13

14 DISCLAIMER The SIS Evolution Realizations presented on the following slide present some of the possible options being considered for G2G. The evolved G2G SIS Evolution for OS is currently under consolidation and may include or not some of the presented ideas plus others not addressed in this presentation. 15/11/2017 Slide 14

15 SIS Evolution Study Case Low Complexity, Fast Acquisition Signal Potential Applications: IoT, handheld mobile, low-end Rx in general, with standalone/assisted operation and snapshot (primary)/continuous (secondary) processing Existing constraints in E1-B/C CBOC(6,1,1/11) spreading symbol PRN code length of 4092 chips Secondary overlay code on E1-C Possible improvement through Low Complexity, Fast Acquisition Signal Possible use cases in the Rx processing: Fast acquisition of E1-B/C and time ambiguity resolution Pilot (or quasi-pilot) component. Quasi-pilot would be used to help resolve time ambiguity E1-B/C provides more precise range measurements and nav message Self-contained for assisted Rx with two potential alternatives: Pilot (or quasi-pilot) able to resolve time ambiguity Pilot + complementary data able to resolve time ambiguity at PRN-processing level Self-contained for standalone (non-assisted) Rx Pilot (or quasi-pilot) + complementary data for fast acq, fast time ambiguity resolution and data demodulation Additional study cases in similar direction are being investigated also within ESA and EC activities 15/11/2017 Slide 15

16 SIS Evolution Study Case Advanced Data Delivery Signal Potential Applications: IoT, handheld mobile, low-end Rx in general. Provision of fast TTFF and advanced data capabilities (higher data rate, robustness, ) Existing constraints in E1-B (I/NAV) Limited spare capacity for additional service data Improved (after I/NAV evolution) but limited data delivery capability (sensitivity, TTFFD) in challenging environment Possible improvement through Advanced Data Delivery Signal Possible use cases in the Rx processing: Complement of E1-B enabling (conventional CED not provided in this study case): Super-Fast TTFF for low-energy reduced accuracy Provision of Long Term Ephemeris (or improved almanac) Data provision for enhanced authentication capability Time ambiguity resolution in snapshot mode Additional capacity for future usage (real-time, near-real time data dissemination ) Standalone data channel enabling: Bullets of point #1 plus the following capabilities Improved TTFF with nominal accuracy Additional study cases in similar direction are being investigated also within ESA and EC activities 15/11/2017 Slide 16

17 SIS Evolution Study Case Advanced Data Delivery Signal Derived study targets for this study case Study Target Value Justification Clock & Ephemeris Data (CED) dissemination TTFFD cold start Data Demodulation Threshold << 10s 15 db-hz (data-only) To address evolving user needs Authentication dissemination Update period for the ranging authentication Update period for the message authentication << 30s [TBC] << 30s [TBC] From new authentication study targets From new authentication study targets Flexibility To allow seamless introduction of new services TBD (as much as possible) System Objective to allow seamless updates Other non-ced (nced) UTC, iono model, LTE, etc. TBD To support standalone GNSS service 15/11/2017 Slide 17

CED field (i.e. the equivalent of the current 4 I/NAV pages) η = Framing efficiency T CED T CED +T nced = T CED T p Two main design drivers and T/O CED Robustness vs.

18 SIS Evolution Study Case Advanced Data Delivery Signal Three fields considered to design message pages : 1. Configuration Header (CH) to describe the physical layer parameters (e.g., FEC coding rate, symbol rate) of the succeeding non-ced field 2. non-ced field (i.e. all dissemination data not related to the first field) 3. CED field (i.e. the equivalent of the current 4 I/NAV pages) η = Framing efficiency T CED T CED +T nced = T CED T p Two main design drivers and T/O CED Robustness vs. TTFF CED Robustness vs Flexibility (and nced throughput) higher framing efficiency brings higher robustness but less flexibility for updates 15/11/2017 Slide 18

SIS Evolution Study Case Advanced Data Delivery Signal Option 1 : 12s page at 250 sps CED (8s): ~

with r=1/3 Efficiency ratio: 4/6 = 66% Option 3 : 4s page at 1000 sps CED (2s): ~ 600 bits with

for option 3 (short pages at 1000sps) lower TTFF in both AWGN and LMS channels good robustness

19 SIS Evolution Study Case Advanced Data Delivery Signal Option 1 : 12s page at 250 sps CED (8s): ~ 600 bits with r=1/3 Efficiency ratio: 8/12 = 66% Option 2 : 8s page at 500 sps CED (4s): ~ 600 bits with r=1/3 Efficiency ratio: 4/6 = 66% Option 3 : 4s page at 1000 sps CED (2s): ~ 600 bits with r=1/3 Efficiency ratio: 2/3 = 66% GPS L1C assumes Data + Pilot The results highlight an advantage for option 3 (short pages at 1000sps) lower TTFF in both AWGN and LMS channels good robustness thanks to accumulation (and time diversity) and optionally : high rate nced for low latency 15/11/2017 Slide 19

20 SIS Evolution Study Case Improved Authentication at Range Level OS-NMA is a good staring point and can be further enhanced with the objective to provide improved evidence on correctness of the obtained range measurements Different Range level verification methods are currently studied for the Evolution of Galileo SIS Common Element of Range level verification: Manipulation of physical ranging signal Shall be sufficiently subtile to make it difficult to extract the manipulated sequence by an attacker Shall still be efficiently usable by mass-market users Shall not induce the need for tamper resistant user device Range level verification shall support All user operation modes, incl. the most vulnerable modes (i.e. cold acquisition with timeuncertainty) All user processing modes, incl. lower grade, low energy (i.e. snapshot) users All user positioning modes, related to code and/or carrier-based PVT All relevant environmental modes, incl. also urban Range level verification designed as Galileo self-sufficient feature, i.e. no dependencies to other systems One possible range verification method (among many others): Anti Replay Protection (ARP) 15/11/2017 Slide 20

SIS Evolution Study Case Improved Authentication at Range Level OS Anti-Replay Protection (ARP) Designed as a-posteriori range verification concept exploiting advantages on unpredictability of

User concept of operation for ARP 1. Tracking of Standard OS 2. Sampling of the incoming signal and sample storage 3. Crypto data demodulation from SIS and seed signature verification 4.

21 SIS Evolution Study Case Improved Authentication at Range Level OS Anti-Replay Protection (ARP) Designed as a-posteriori range verification concept exploiting advantages on unpredictability of encrypted PRN codes Provision of encrypted PRN chips (individual bursts or through dedicated, fully encrypted low power componet) to user Key release and transmission through SIS to user with delay User concept of operation for ARP 1. Tracking of Standard OS 2. Sampling of the incoming signal and sample storage 3. Crypto data demodulation from SIS and seed signature verification 4. ARP local replica re-generation 5. Acquisition and tracking of ARP SIS component (available in stored samples) with the locally generated ARP 6. Correlation and verification of the ARP range measurement with Standard OS range measurement 15/11/2017 Slide 21

22 Conclusions and Way Forward Galileo Evolution is advancing Evolution objectives are available Evolution objectives are flown down to different evolution system concepts after extensive Trade-off analyses Technology options identified necessary for Galileo Evolution are under development through pre-developments Open Service Signal in Space Evolution is addressed in form of study cases at ESA and EC level and is under consolidation including also stakeholder and user consultation with the objective to Establish Signal in Space flexibility to allow for reduced time-to-market Improve existing signals/services Enable new services Improve robustness against emerging threats Prepare for emerging user trends The Future of Galileo is materializing! 15/11/2017 Slide 24

23 Thank you!

24 BACKUP MATERIAL 15/11/2017 Slide 26

25 Navigation and Timing Provision Galileo Evolution targets to improve Ranging accuracy between 2 and 5 times wrt Galileo FOC Position accuracy down to sub-meter accuracy Timing accuracy reduced by 2 times wrt Galileo FOC High ranging accuracy enables carrier phase-based positioning (using broadcast ephemeris) Optimized ODTS algorithms (advanced preprocessing, clock and Solar Radiation Pressure modelling) Improved on-board timing technology Ranging from Inter-Satellite Links Improving availability by technology advances 15/11/2017 Slide 27

26 Galileo s Support to Interoperable GNSS Space Service Volume Antenna Gain G1G signal emissions already reach out to space and Galileo space receivers (AGGA4) are already available SSV is not covered by requirements in current Galileo Recommended solution: Characterise existing capabilities and maintain these capabilities through dedicated set of requirements (similar approach as followed by GPS) Implementation: Mask for EIRP Directional Dependency in E1 Actual Capabilities G1G Antenna Characterisation Ground IOT MARGIN Guaranteed Capabilities (earth user) OS SIS-ICD Requirement Identification d EIRP min,e1 (q) d EIRP max,e1 (q) q for 5 elevation Satellite antenna off-boresight angle q [deg] Guaranteed Capabilities (space + earth user) 15/11/2017 Slide 28

OS Anti-Replay Protection SIS Aspects Physical Ranging Signal Full Encryption: chip-by-chip encryption SIS Watermarking: multiplexing of unpredictable chip sequences at random time instances within

27 OS Anti-Replay Protection SIS Aspects Physical Ranging Signal Full Encryption: chip-by-chip encryption SIS Watermarking: multiplexing of unpredictable chip sequences at random time instances within the unencrypted PRN sequence Data Provision to the user Synergies of OS-ARP with OS-NMA can be exploited by a possible re-use of the OS-NMA key scheme for the generation of the OS ARP unpredictable code sequence Timeliness needs are to be met by the data channel providing the necessary crypto elements exploited for OS ARP Additional study cases in similar direction are being investigated also within ESA and EC activities 15/11/2017 Slide 29

Galileo Open Service Navigation Message

Galileo Open Service Navigation Message 31/01/2018 S. Binda - GNSS Interferentie en Authenticatie, Haarlem, NL ESA UNCLASSIFIED - For Official Use GALILEO System Current Status ESA UNCLASSIFIED - For Official