Loading in 2 Seconds...
Loading in 2 Seconds...
GPS Space Service Volume Increasing the Utility of GPS for Space Users Michael C. Moreau, Ph.D. Flight Dynamics Analysis Branch NASA Goddard Space Flight Center October 16, 2008 Outline Background on use of GPS in High Earth Orbits Space Service Volume Definition and Characteristics
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Michael C. Moreau, Ph.D.
Flight Dynamics Analysis Branch
NASA Goddard Space Flight Center
October 16, 2008
Capability Description Document for GPS III includes updated Space Service Volume definition and requirements
Feb, 2000 version of GPS Operational Requirements Document (ORD) includes first requirements for Space Service Volume
Many civil and military missions with plans for operational use of GPS in high altitude orbits…
EQUATOR-S, TEAMSAT, Falcon Gold flight experiments
Kronman paper published on DoD mission using GPS in GEO orbit
STENTOR (GEO) mission lost to launch vehicle failure
NASA/AMSAT AO-40 flight experiment
STRV1-D mission lost to launch vehicle failure
TANS Vector Receiver
High Gain Antenna (1 of 4)
data from II/IIA satellites follows predictions
IIR data has steeper drop-off of main lobe signals, but higher side lobes
Main lobes only (within 23.5 degrees)
All signals above –182 dBW
4 or more SVs visible: 2%
2 or more SVs visible: 31%
no SVs visible : 39%
4 or more SVs visible: 100%
2 or more SVs visible: 100%
no SVs visible : 0%
AO-40 data affirmed GPS side lobe signals significantly improve signal availability
GPS IIF Operational Requirements Document (ORD)
Evolving Space User Requirementscontinued
Periods or 2 or more GPS available35 dB-Hz sensitivityEI – 2 hrs
GPS altitudeEI – 1.2 hrs
Final Correction Burn, EI-5 hrs
Periods 2 or more GPS available25 dB-Hz sensitivityEI – 12 hrs
Correction BurnEI-16 hrs
F.H. Bauer, M.C. Moreau, M.E. Dahle-Melsaether, W.P. Petrofski, B.J. Stanton, S. Thomason, G.A Harris, R.P. Sena, L. Parker Temple III, The GPS Space Service Volume, ION GNSS, September 2006.
M.Moreau, E.Davis, J.R.Carpenter, G.Davis, L.Jackson, P.Axelrad, “Results from the GPS Flight Experiment on the High Earth Orbit AMSAT AO-40 Spacecraft," Proceedings of the ION GPS 2002 Conference, Portland, OR, 2002.
Kronman, J.D., "Experience Using GPS For Orbit Determination of a Geosynchronous Satellite," Proceedings of the Institute of Navigation GPS 2000 Conference, Salt Lake City, UT, September 2000.
These and other NASA References can be found here: