Task Force On The Future of the Global Positioning System (extract) DSB Task Force on the Future of the Global Positioning System
National PNT Objectives* Provide uninterrupted availability of positioning, navigation, and timing services Meet growing national, homeland, economic security, and civil requirements, and scientific and commercial demands Remain the pre-eminent military space-based positioning, navigation, and timing service Continue to provide civil services that exceed or are competitive with foreign civil space-based positioning, navigation, and timing services and augmentation systems Remain essential components of internationally accepted positioning, navigation, and timing services Promote U.S. technological leadership in applications involving space- based positioning, navigation, and timing services * Source: U.S. Space-based Positioning, Navigation, and Timing Policy, NSPD Signed by President Bush, 15 December 2004 DSB Task Force on the Future of the Global Positioning System
Salient Points from Task Force The service provided to users is crucial—not sub-optimizing the satellite component GPS is a system-of-systems. Satellites, operational control segment & receivers must be effectively integrated Minimum constellation size should be 30 satellites—to better support ground forces in varied terrain Ambitious requirements are driving the cost of GPS III –Cost & weight must be controlled –Dual launch essential Relax emphasis on anti-spoof. Increase attention to anti-jam Time & attention must be given to maintain GPS as world’s premier satellite navigation. Governance needs adjustment & improvement—open-minded approach is necessary in considering options DSB Task Force on the Future of the Global Positioning System
Mask Angle Effects DSB Task Force on the Future of the Global Positioning System 5o5o 15 o X X 5o5o (30-1) (24-1) (24-2) (24-3) (24-5) (24-4) (24-6) Assumes 1 m User Range Error Differences caused by Geometric Dilution of Precision effects (DOP x URE = Accuracy)
GPS III Launch Costs EELV Costs: EELV-L=$75M; EELV-M=$90M; EELV-H=$150M (Buy #1) EELV-L=$150M; EELV-M=$180M; EELV-H=$300M (Buy #3 – in Source Selection) Failure Rates: 4% Single; 5% Dual (Source: GPS JPO Study, 20 Jul 05) DSB Task Force on the Future of the Global Positioning System