Welcome to Stanford! Civil Aviation Administration of China

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Welcome to Stanford!Civil Aviation
Administration of China Federal Aviation
Administration
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Welcome to Stanford

• Ms. Lu Xiao Ping, Deputy Director General, ATMB
• Ms. Zhang Jing, Director, Inter. Cooperation
  Division, ATMB
• Mr. Li Xin, Director, RD Division, ATMB
• Mr. Pan Yong Dong, Deputy Director, Planning
  Division, ATMB
• Mr. Cao Hui, Manager, Aeronautical Data
  Communication Company
• Mr. Cai KaiQuan, Engineer, ADCC
• Mr. Shi Le, Engineer, ADCC
• Mr. Chris Dufresne, Computer Engineer, FAA
• Mr. CJ Jones, FAA / ATO
• Mr. Dave Burkholder, FAA / ATO
• Mr. Sam El-Zoobi, FAA / ATO
• Mr. J.C. Johns, Navigation Director, FAA

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Agenda

• 730     Parking and Logistics
• 800 Welcome from the FAA ATO International, Mr.
  David Burkholder
• 815 Introductory Remarks and GPS/RAIM
  Objectives, Madame Lu
• 830 Overview of FAA Satellite Navigation, Mr.
  J.C. Johns
• 845 History of Stanford Involvement with FAA
  SatNav, Prof Per Enge
• 900 Absolute RAIM, Dr. Todd Walter
• 930 Break
• 945 Civil Monitoring, Dr. Xingxin Gao
• 1015 GPS Modernization, Prof. Brad Parkinson
• 1045 Open discussion on potential for GPS RAIM
  cooperation between FAA, Stanford and CAAC ATMB
• 1130 Lunch at the Faculty Club
• 100 Closing Remarks and document agreed to Next
  Steps for presentation at JATSG/6 on 4/21  (FAA,
  ATMB and Stanford)

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History of Stanford Involvement with FAA
Satellite Navigation From 1990 to the GEAS for
the Civil Aviation Administration of Chinaby Per
Enge (with the help of many)April 20, 2009
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The Global Positioning System
User Segment
Control Segment
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Stanford Scope Maximize Aviation Benefits from
GNSS

• Worldwide approach capability with vertical
  guidance, but no airport equipment.
• Worldwide landing capability (Cat. I/II/III) with
  high availability.
• Robust against
• Faults
• Rare normal
• Ionosphere
• Scheduled RFI
• Unscheduled RFI
• Safety Analyses

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Very Brief History of Stanford Work for the FAA
2000
2010
1990
Brad Parkinson gathers a GPS team at
Stanford Early work on LADGPS, WADGPS
RAIM LADGPS flight trials based on in-track
pseudolites WADGPS flight trials based on vector
corrections Co-chair RTCA WG-4 LADGPS flight
trials based on airport pseudolites Work on
operational benefits Tunnel in the sky displays,
wake vortex, CSPA, etc. Design for safety
faults rare normal events Interaction with
prime contractors WAAS integrity performance
panel (WIPP co-chairs) LAAS integrity
performance panel (LIPP)
WAAS Operational
LAAS Operational
All of the above was funded by the FAA through
Cooperative Agreements 93-G-004, 95-G-005,
97-G-012, 00-G-012 08-G-007.
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First 10 Years Focused on Flight Trials
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Second 10 Years Faults Rare Normal Events
October 1993 modulation fault
Clock runoffs 7/28/01, 5/26/03 6/11/03 more
40 notable iono events during the last solar peak

• RFI events
• San Diego
• St Louis
• Santa Cruz

April 10, 2007 ephemeris fault 24 smaller
faults over the last 5 years
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Truncation of the Error Tail
ground screening (Cat I)
air ground screening (Cat I/II/III)
dual freq. GBAS (Cat I/II/III)
PDF
0
5
10
15
20
25
30
35
40
45
User Vertical Position Error (meters)
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Evolution of GNSS-Based Safety
2020
2030
2010

• L1 Only
• RAIM
• SBAS
• GBAS

• Dual freq. SBAS GBAS
• 24 SVs Minimum
• 10-4 from GNSS
• Dual freq. ARAIM
• Open service
• GPS 30 Slots
• Multi-constellation
• 10-4 from GNSS

• GNSS Integrity Within
• GPS IIIC (1st 16) , or
• GNSS Safety of Life
• 24 SVs (GPS alone)
• 10-7 from GNSS

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Our Current Emphasis L5 New Constellations
2020
2030
2010

• Dual freq. SBAS GBAS
• 24 SVs Minimum
• 10-4 from GNSS
• Dual freq. ARAIM
• Open service
• GPS 30 Slots
• Multi-constellation
• 10-4 from GNSS

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Absolute Receiver Autonomous Integrity Monitoring
(ARAIM) for 2020
GPS
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FAA Supported Graduates of the GPS Lab (1/2)

• University Professors
• Penny Axelrad, UColorado
• Changdon Kee, SNU
• Boris Pervan, IIT
• Glenn Lightsey, UT Austin
• Demoz Gebre-Egziabher, UMinn.
• Gabe Elkaim,f UCSC
• Shau-Shiun Jan, Taiwan
• David Bevly, Auburn U.
• Novariant
• Clark Cohen
• Stewart Cobb
• Dave Lawrence
• Paul Montgomery
• Mike O'Connor
• Tom Bell
• Frank Bauregger
• Televigation, Y.C. Chao

• Traxis
• Roger Hayward
• Jock Christie
• Rich Fuller
• Nav3D
• Andy Barrows
• Keith Alter
• Chad Jennings
• Rossum
• Matt Rabinowitz
• Guttorm Opshaug
• Ju-yong Do
• M Shift, Awele Ndili
• Mapbar.com, Donghai Dai
• Meta-VR, Andrew Hansen
• NordNav
• Per-Ludwig Normark
• Sasha Mitelman
• OlinkStar, Junlin Zhang

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FAA Supported Graduates of the GPS Lab (2/2)

• Medium Size Companies
• Jiyun Lee
• Ping-Ya Ko
• Yeou-Jyh Tsai
• Jaewoo Jung
• Gang Xie, SiRF
• Alexander Mitelman, NordNav
• Ung-Suok Kim
• Michael Koenig, SiRF
• Lee Boyce Consultant
• Seebany Datta-Barua, ASTRA
• Euiho Kim, Wilcox
• Hiroyuki Konno, TopCon
• Harris Teague, Seagull
• Sharon Houck, Seagull

• University or Govt. Researchers
• Sam Pullen
• Eric Phelts
• Sherman Lo
• Juan Blanch
• Konstantin Gromov, JPL
• Eric Olsen, Johns Hopkins APL
• Jenny Gautier, UC
• Ran Gazit, Rafael
• Hiro Uematsu, NASDA
• Andrew Hansen, FAA Volpe
• Large Companies
• Andy Rekow, John Deere
• Eric Abbott L3

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Updated Stanford Work Plan for FY09for JC
Johnsby Per Enge (with the help of many)April
20, 2009
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Evolution of GNSS-Based Safetyfrom the GEAS
2020
2030
2010

• L1 Only
• RAIM
• SBAS
• GBAS

Task 1 Optimize Single Frequency WAAS Task 2
SDM from WAAS to LAAS Task 3 GAST-D Task 4 DCPS
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Task 1 Optimize Single Frequency WAAS

• Provide added robustness for upcoming solar
  maximum
• Work with Raytheon to implement kriging
• Retune algorithms and storm detectors to ensure
  maximum CONUS availability
• Work with Raytheon to implement improved SQM for
  better continuity
• Provide training to Oklahoma City to ensure they
  understand intent and design of WAAS algorithms

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Task 2 Use WAAS SDM to Validate Nominal Model
for New LAAS SVs
SV11 23 cause LAAS SDM to trip during
SLS4000 development
WAAS SDM Trip Threshold
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Task 2 Use WAAS SDM to Validate Nominal Model
for New LAAS SVs
From WAAS PAN report Increasing trend used to
confirm SLS-4000 SDM was operating correctly by
flagging and excluding PRN 11.
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Task 3 GAST-D is Seeking Iono FreedomIonosphere
Anomaly Threat Model
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Task 3 GAST-DTruncates the Error Tail
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Task 3 GAST-DTruncates the Error Tail
ground screening (Cat I)
air ground screening (Cat I/II/III)
dual freq. GBAS (Cat I/II/III)
PDF
0
5
10
15
20
25
30
35
40
45
User Vertical Position Error (meters)
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Task 3 GAST-D Availability Tool
LAAS ground and user PR error models
GPS SV almanac
Loop through all time epochs over 1 day
Loop through 12 U.S. airport locations
Loop through all outage cases (0, 1, 2, 3 SV out)
Compute User Protection Levels for current SV
geometry
Are GAST-D reqts. met?
Increment availability counters terminate
outage counters
Yes
No
Increment outage counters

• Availability requires
• VPL 10-meter VAL
• max. Svert constraints met
• max Svert ? 3.0
• max Svert 2nd max Svert ? 5.0

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Task 3 GAST-D Availability vs Constellation
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Task 3 GAST-D (L1-only CAT II/III)

• Fall 2008 review led by Jason Burns John
  Warburton
• SU, IIT, other KTAs reviewed GAST-D technical
  status
• Identified issues that need further study (e.g.,
  multiple faults, time-to-alert)
• SU supporting FAA review of ionosphere anomaly
  mitigation alternatives
• ICAO/RTCA technical concept validation desired by
  end of 2009

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Task 4 DCPS

• Latest LAAS MOPS (DO-253C) limits DCPS to
  horizontal navigation (i.e., no VPL for DCPS)
• Further changes needed - seek best combination of
  several options
• Implement a screening HAL of 50 200 meters ?
  below this value, HPL is not guaranteed to bound
  worst-case HPE
• Add airborne geometry screening via max. Shoriz
  (similar to GAST-D), min. Nsat, or max.
  (NLGF_corr Nsat)
• Add airborne RAIM integrity monitoring (for DCPS
  only)
• These include changes to MOPS and to iono. threat
  model (relative to PA ? 1 SV impact only)

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Evolution of GNSS-Based Safety
2020
2030
2010

• Dual freq. SBAS GBAS
• 24 SVs Minimum
• 10-4 from GNSS

Task 5 Dual freq WAAS (L5 Roadmap) Task 6 Dual
freq GBAS JPALS
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Aviation Benefits from New Constellations
Signals

• Worldwide approach capability with vertical
  guidance, but no airport equipment.
• Worldwide landing capability (Cat. II/III) with
  high availability.
• Robust against
• Ionosphere
• Scheduled RFI
• Unscheduled RFI
• Malevolent RFI

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Task 5 Dual Frequency WAASConvert Orange to
Green
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Task 5 Dual Frequency WAAS

• Finalize support the L5 transition plan based
  on
• L5 roadmap meetings
• L2 semi-codeless sunset
• Support L1/L5 avionics
• Meetings with service providers, RTCA Eurocae
• Publish scintillation white paper based on
• International working group
• Jiwon Seo outage statistics correlation
• Tsung-Yu Chiou receiver design
• L5 SBAS MOPS development at RTCA EUROCAE
• Determination of message contents and formats
• Determination of user algorithms
• Coordination with receiver manufacturers

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Task 6 Dual-Freq. LAAS Combines Divergence-Free
Ionosphere-Free Smoothing
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Task 6 Land-Based JPALS Ground Facility
Changed to divergence-free (DF) smoothing in
LDGPS iono-free (IF) smoothing and LAAS-like SF
smoothing are backups
In JPALS, adjust thresholds based on observed
local RF interference
Removed in JPALS air and ground receivers have
similar designs
JPALS includes multiple corrections for L1 vs. L2
and different smoothing types
Multiple sets of B-values are computed and
monitored
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Evolution of GNSS-Based Safety
2020
2030
2010

• Dual freq. ARAIM
• Open service
• GPS 30 Slots
• Multi-constellation
• 10-4 from GNSS

• GNSS Integrity Within
• GPS IIIC (1st 16) , or
• GNSS Safety of Life
• 24 SVs (GPS alone)
• 10-7 from GNSS

Task 7 System Def., Requirements PL
equations Task 8 Experimental Validation Task 9
International outreach Task 10 F/A-18 Hornet
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Task 7 System DefinitionARAIM for 2020
GPS
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Task 7 System DefinitionARAIM for 2020
Compass
GLONASS
GPS
Compass
GLONASS
Galileo
GPS
Compass
GLONASS
Galileo
GPS
Compass
GLONASS
Galileo
GPS
Compass
GLONASS
Galileo
GPS
Galileo
dual frequency open service
Ground Monitors
Air Traffic Status
Ground Control

1. How do we close the loop? through Air Traffic
2. What do we ground monitor? URA biases
3. How often do we close the loop? once per hour
4. What monitor network do we use? civil monitoring
   net
5. What do we ask of other service providers? same
   as us

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Task 7 System Definition2030 GPSIII C
GLONASS
Compass
GPS
Compass
GLONASS
Galileo
GPS
Compass
GLONASS
Galileo
GPS
Compass
GLONASS
Galileo
GPS
GLONASS
Compass
Galileo
GPS
Galileo
dual frequency PPS
Ground Monitors
Ground Control

1. How do we close the loop? through the GPS SVs
2. What do we ground monitor? ephemeris URA to
   10-7
3. How often do we close the loop? once per minute
   (RRAIM)
4. What monitor network do we use? GPS
5. What do we ask of other GNSS service providers?
   Not so much (ARAIM?)

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Task 7 Proposed VPL Equations

• GPS IIIC
• ARAIM

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Task 7 Proposed Translation from Probabilities
to Ground Monitoring
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Task 7 Assertions Under Consideration

• 1. Ergodicity
• 2. Smoothness
• 3. Short Temporal Correlations
• 4. Symmetry
• 5. Independence of Errors
• 6. Full Threat Analysis
• 7. Corrective Action

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Task 7 System Definition, Requirements
Protection Level Equations

• Continue work briefed by Todd Walter at February
  2009 GEAS
• Finalize URE definition
• Finalize URA monitoring
• PL equations for multi-constellation ARAIM
• PL equations for GPS IIIC
• Seek wider review
• Coordinate with PSICA group to ensure FAA
  assurance requirements are being monitored and
  met.

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Task 8 Validate Civil Monitoring(Collaboration
with FAATC AMTI)

• Civil monitoring is a trade between
• Constellation size
• Robustness to SV failures
• Network size (URA bounding)

ARAIM 99.5 coverage 24-1 24 27-1 27 30-1 30
No Real Time Monitoring 3.7 27.5 9.56 87.9 79.8 99.6
8 stations 50.8 88.3 71.5 96.7 98.7 100
38 stations 71.2 98.9 90.0 100 99.9 100
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Task 8 Validate Civil Monitoring of
Signals(Collaboration with FAATC AMTI)
Cavity Filter
Low NoiseAmplifier
15 m cable
45dB
Digital filter bank with control circuits
Azimuth/Elevation Control
Automatic data recording based on triggers
Agilent Vector Signal Analyzer (VSA)
Nova for Windows Satellite Tracking Software
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Task 8 Validate Civil Monitoring of
Measurements(Collaboration with FAATC AMTI)

• Objectives
• Nominal range errors URE
• Detect characterize range error URE blunders
• Challenges
• Compute range error without post-processed truth
• Volume of data and computational load
• Milestones
• MATLAB Interface is ready
• Integrate the algorithm within the current
  monitoring
• Migration from nationwide network to worldwide
  network
• Migration from L1/L2 to L1/L5

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Task 8 Validate Flight Performance
Undetected Fault
Detection Process
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Task 9 International Outreach to Enable
Multi-Constellation ARAIM

• Key common understanding of providers
  responsibility
• All parties need to participate in requirement
  development
• Each constellation can choose level of
  performance
• Performance must be monitored to enable ARAIM
• New document for constellation requirements
• New document for avionics requirements
• MOPS SARPS
• PL equations
• Message contents

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Task 9 International Outreach(Schedule for next
4 months)

• March 2-3 ICG Workshop on GNSS Interoperability
  Benefits of multi-constellation ARAIM and
  requirements from GNSS service providers
• March 3-5 Munich Satellite Summit GEAS vision
  and benefits of multi-constellation ARAIM
• March 25-26 First meeting of Working Group C on
  interoperability of integrity service provision.
• April 2-4 Outreach to African nations on GNSS -
  aviation applications and the importance of
  understanding ionospheric behavior.  Emphasis on
  getting measurements during the upcoming solar
  maximum.
• April 2-4 SBAS iono working group meeting.
• April 20 Civil Aviation Administration of China
  ATMB will visit Stanford (HoD Deputy Director
  Madam Liu)
• April 21-23 Eurocae WG-62 is having substantial
  discussion on the use of multi-constellation
  ARAIM for vertical guidance.
• May or June IWG to be hosted at Stanford.  Will
  discuss L5 plans
• June 23 RTCA WG-2 need to start serious work on
  L5 MOPS

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Task 10 Naval Aviation Enterprise has use for
LPV worldwide.

• What research or study is
• required to certify the system?
• Joint testing?
• ARAIM with one constellation
• SBAS in coverage
• SBAS/ARAIM in mixed
• WAGE based URE
• Availability/integrity
• requirements in theatre
• TIM at Stanford in early April

F/A-18 Hornet
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Optional Task 11 Security Against DoS
Spoofing AttacksTri-lateration Based on Mode-S
Bring the safety perspective early on. What VALs
HALs can be supported? Preliminary FMEA