© 2014 The MITRE Corporation. All rights reserved. SBAS IWG #26 Meeting Delhi, India 5-7 February 2014 Roland Lejeune RTCA SC-159 Working Group 2 Summary of Recent Meetings

| 2 || 2 | Introduction  One RTCA SC-159 WG2 meeting took place since IWG/25: –October 8-9, 2013  Main items addressed by WG2: –System status updates –Harmonization of SARPs and MOPS requirements –Outcome of meeting in Russia regarding GLONASS mandate –GNSS “score card” –GNSS Evolution  Reducing errors from signal deformations  Correcting for time offsets between constellations  Robustness to ionospheric scintillation effects  Concept of Operation for GPS/GALILEO receiver  Work plan for GPS L1/L5 receiver and multi-constellation receiver © 2014 The MITRE Corporation. All rights reserved.

| 3 || 3 | Summary of discussions (1 of 4)  System status updates –EGNOS, Galileo  Harmonization of SARPs and MOPS requirements –Updated NSP paper provided for review  Outcome of meeting in Russia regarding GLONASS mandate –Representatives from FAA, Boeing, Airbus, some manufacturers met with Russian civil aviation authorities in Moscow, May 22-23, to obtain clarifications on Russian mandate –Meeting revealed differences in perspectives and on information needed for implementation in aircraft –But also a common desire to collaborate towards a multi- constellation standard © 2014 The MITRE Corporation. All rights reserved.

| 4 || 4 | Summary of discussions (2 of 4)  GNSS “score card” –Initial version developed by Laurent Azoulai (Airbus)  On basis of list of questions developed earlier by EUROCAE –Documents extent to which information needed to support the development of avionics MOPS is available for GNSS core constellations that are, or will be, standardized in Annex 10  GPS, Galileo, Galileo, BeiDou  Expected to be completed for GPS and Galileo for December 2013 EUROCAE meeting  Information from Chinese and Russian providers requested –Note: when score card was discussed at NSP, Russian and Chinese delegations indicated that they will help fill the score card for their constellations © 2014 The MITRE Corporation. All rights reserved.

| 5 || 5 | Summary of discussions (3 of 4)  GNSS Evolution –Proposal from Todd Walter and colleagues to further limit correlation trade space of future receivers to reduce errors from nominal signal deformation  If reference and user receivers are affected by signal deformation the same way, the corresponding post-correction errors affect the clock solution, not the position solution –Paper from Thales on the inadequacy of the Message Type 12 data to correct for time offsets between different constellations  Data does not account for receiver front-end time delay differences, which can result in errors of several meters –Robustness to ionospheric scintillation effects  Consideration being given to a requirement for fast re-acquisition following a loss-of-lock event triggered by ionospheric scintillation –For future DFMC receivers © 2014 The MITRE Corporation. All rights reserved.

| 6 || 6 | Summary of discussions (4 of 4)  GNSS Evolution (continuation) –Concept of Operation for GPS/GALILEO receiver  ConOps developed by EUROCAE will be made available to WG2 –Work plan for GPS L1/L5 receiver and multi-constellation receiver  WG2 plans to develop performance requirement in stepwise fashion starting from EUROCAE ConOps –Initial focus on L1/L5 GPS followed by an expansion to multi- constellation  Effort will attempt to capture operational benefits –WG2 agreed to start working actively on a document  To capture the technical concept of operations and requirements for a L1/L5 GPS and L1/L5 SBAS receiver  Not yet a MOPS, but a basis for future MOPS development © 2014 The MITRE Corporation. All rights reserved.

| 7 || 7 | Acronyms  FAAFederal Aviation Administration  DFMCDual-Frequency, Multi-Constellation  GNSSGlobal Navigation Satellite System  MOPSMinimum Operational Performance Standard  NSPNavigation System Panel  SARPsStandards and Recommended Practices  SBASSatellite-Based Augmentation System  WG2Working Group 2 © 2014 The MITRE Corporation. All rights reserved.