The Global Positioning System (GPS), is an intermediate circular orbit (ICO) satellite navigation system used for determining one's precise location and providing a highly accurate time reference almost anywhere on Earth. The satellites in the GPS constellation are called NAVSTAR (Navigation System using Timing And ranging).
The system consists of a "constellation" of at least 24 satellites in 6 orbital planes. Each satellite circles the Earth twice every day at an altitude of 20,200 kilometers. The satellites carry atomic clocks and constantly broadcast the precise time according to their own clock, along with administrative information including the orbital elements of their own motion, as determined by a set of ground-based observatories.
There are two frequencies in use: 1575.42 MHz (referred to as L1), and 1227.60 MHz (L2). The L1 signal carries a publicly usable coarse-acquisition (C/A) code as well as an encrypted P(Y) code. The L2 signal usually carries only the P(Y) code. The keys required to directly use the P(Y) code are tightly controlled by the U.S. government and are generally provided only for military use.
The GPS system included following generations of GPS satellites:
Series | Generation | Number | Launched | Lifetime | Mass (Launch) | Manufacturer | Launch Vehicles | Remarks | |
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NTS 2 | Prototype | 1 | 1977 | 431 kg | Naval Research Laboratory | Atlas-E/F SGS-1 | ||
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GPS (Navstar) | 1. | 11 | 1978 - 1985 | 759 kg | Rockwell | Atlas-E/F SGS-1 Atlas-E/F SGS-2 |
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GPS-2 (Navstar-2) | 2. | 9 | 1989 - 1990 | 1660 kg | Rockwell | Delta-6925 | ||
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GPS-2A (Navstar-2A) | 2. | 19 | 1990 - 1997 | 1816 kg | Rockwell | Delta-7925 | ||
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GPS-2R (Navstar-2R) | 2. | 13 | 1997 - 2004 | 2032 kg | Lockheed Martin | Delta-7925 | ||
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GPS-2RM (Navstar-2RM) | 2. | 8 | 2005 - 2008 | 2032 kg | Lockheed Martin | Delta-7925 | ||
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GPS-2F (Navstar-2F) | 2. | 12 | 2010 - 2014 | 15 | 1545 kg | Boeing | Atlas-5(401)
Delta-4M+(4,2) |
Direct orbit insertion |
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GPS-3 (Navstar-3) | 3. | 10 | planned 2018 | 4400 kg | Lockheed Martin | Atlas-5(411)¹
Delta-4M+(4,2) (upg.) Falcon-9 v1.2 (Block 5) |
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GPS-3F (Navstar-3F) | 3. | 22 | planned 2026 | ? kg | Lockheed Martin |
Satellite | Date | LS | Launcher | Remarks: | |
---|---|---|---|---|---|
NTS 2 (P76-4) | 23.06.1977 | Va SLC-3W | Atlas-F SGS-1 | ||
GPS 1 (Navstar 1, OPS 5111) | 22.02.1978 | Va SLC-3E | Atlas-F SGS-1 | ||
GPS 2 (Navstar 2, OPS 5112) | 13.05.1978 | Va SLC-3E | Atlas-F SGS-1 | ||
GPS 3 (Navstar 3, OPS 5113) | 07.10.1978 | Va SLC-3E | Atlas-F SGS-1 | ||
GPS 4 (Navstar 4, OPS 5114) | 11.12.1978 | Va SLC-3E | Atlas-F SGS-1 | ||
GPS 5 (Navstar 5, OPS 5117) | 09.02.1980 | Va SLC-3E | Atlas-F SGS-1 | ||
GPS 6 (Navstar 6, OPS 5118) | 26.04.1980 | Va SLC-3E | Atlas-F SGS-1 | ||
GPS 7 (Navstar 7) | 19.12.1981 | Va SLC-3E | F | Atlas-E SGS-1 | |
GPS 8 (Navstar 8, OPS 9794) | 14.07.1983 | Va SLC-3W | Atlas-E SGS-2 | ||
GPS 9 (Navstar 9, USA 1) | 13.06.1984 | Va SLC-3W | Atlas-E SGS-2 | ||
GPS 10 (Navstar 10, USA 5) | 08.09.1984 | Va SLC-3W | Atlas-E SGS-2 | ||
GPS 11 (Navstar 11, USA 10) | 08.10.1985 | Va SLC-3W | Atlas-E SGS-2 | ||
GPS-2 0 (Navstar 12) | not launched | ||||
GPS-2 1 (Navstar 14, USA 35) | 14.02.1989 | CC LC-17A | Delta-6925 | ||
GPS-2 2 (Navstar 13, USA 38) | 10.06.1989 | CC LC-17A | Delta-6925 | ||
GPS-2 3 (Navstar 16, USA 42) | 18.08.1989 | CC LC-17A | Delta-6925 | ||
GPS-2 4 (Navstar 19, USA 47) | 21.10.1989 | CC LC-17A | Delta-6925 | ||
GPS-2 5 (Navstar 17, USA 49) | 11.12.1989 | CC LC-17B | Delta-6925 | ||
GPS-2 6 (Navstar 18, USA 50) | 24.01.1990 | CC LC-17A | Delta-6925 | ||
GPS-2 7 (Navstar 20, USA 54) | 25.03.1990 | CC LC-17A | Delta-6925 | ||
GPS-2 8 (Navstar 21, USA 63) | 02.08.1990 | CC LC-17A | Delta-6925 | ||
GPS-2 9 (Navstar 15, USA 64) | 01.10.1990 | CC LC-17A | Delta-6925 | ||
GPS-2A 1 (Navstar 23, USA 66) | 26.11.1990 | CC LC-17A | Delta-7925 | ||
GPS-2A 2 (Navstar 24, USA 71) | 04.07.1991 | CC LC-17A | Delta-7925 | with Losat X | |
GPS-2A 3 (Navstar 25, USA 79) | 23.02.1992 | CC LC-17B | Delta-7925 | ||
GPS-2A 4 (Navstar 28, USA 80) | 10.04.1992 | CC LC-17B | Delta-7925 | ||
GPS-2A 5 (Navstar 26, USA 83) | 07.07.1992 | CC LC-17B | Delta-7925 | ||
GPS-2A 6 (Navstar 27, USA 84) | 09.09.1992 | CC LC-17A | Delta-7925 | ||
GPS-2A 7 (Navstar 32, USA 85) | 22.11.1992 | CC LC-17A | Delta-7925 | ||
GPS-2A 8 (Navstar 29, USA 87) | 18.12.1992 | CC LC-17B | Delta-7925 | ||
GPS-2A 9 (Navstar 22, USA 88) | 02.02.1993 | CC LC-17A | Delta-7925 | ||
GPS-2A 10 (Navstar 31, USA 90) | 29.03.1993 | CC LC-17A | Delta-7925 | with SEDS 1 | |
GPS-2A 11 (Navstar 37, USA 91) | 14.05.1993 | CC LC-17A | Delta-7925 | ||
GPS-2A 12 (Navstar 39, USA 92) | 26.06.1993 | CC LC-17A | Delta-7925 | with PMG | |
GPS-2A 13 (Navstar 35, USA 94) | 30.08.1993 | CC LC-17B | Delta-7925 | ||
GPS-2A 14 (Navstar 34, USA 96) | 26.10.1993 | CC LC-17B | Delta-7925 | ||
GPS-2A 15 (Navstar 36, USA 100) | 10.03.1994 | CC LC-17A | Delta-7925 | with SEDS 2 | |
GPS-2A 16 (Navstar 33, USA 117) | 28.03.1996 | CC LC-17B | Delta-7925 | ||
GPS-2A 17 (Navstar 40, USA 126) | 16.07.1996 | CC LC-17A | Delta-7925 | ||
GPS-2A 18 (Navstar 30, USA 128) | 12.09.1996 | CC LC-17A | Delta-7925 | ||
GPS-2R 1 (Navstar 42) | 16.01.1997 | CC LC-17A | F | Delta-7925 | |
GPS-2R 2 (Navstar 43, USA 132) | 23.07.1997 | CC LC-17A | Delta-7925 | ||
GPS-2A 19 (Navstar 38, USA 135) | 06.11.1997 | CC LC-17A | Delta-7925 | ||
GPS-2R 3 (Navstar 46, USA 145) | 07.10.1999 | CC SLC-17A | Delta-7925 | ||
GPS-2R 4 (Navstar 51, USA 150) | 11.05.2000 | CC SLC-17A | Delta-7925 | ||
GPS-2R 5 (Navstar 44, USA 151) | 16.07.2000 | CC SLC-17A | Delta-7925 | ||
GPS-2R 6 (Navstar 41, USA 154) | 10.11.2000 | CC SLC-17A | Delta-7925 | ||
GPS-2R 7 (Navstar 54, USA 156) | 30.01.2001 | CC SLC-17A | Delta-7925 | ||
GPS-2R 8 (Navstar 56, USA 166) | 29.01.2003 | CC SLC-17B | Delta-7925 | with XSS 10 | |
GPS-2R 9 (Navstar 45, USA 168) | 31.03.2003 | CC SLC-17A | Delta-7925 | ||
GPS-2R 10 (Navstar 47, USA 175) | 21.12.2003 | CC SLC-17A | Delta-7925 | ||
GPS-2R 11 (Navstar 59, USA 177) | 20.03.2004 | CC SLC-17B | Delta-7925 | ||
GPS-2R 12 (Navstar 60, USA 178) | 23.06.2004 | CC SLC-17B | Delta-7925 | ||
GPS-2R 13 (Navstar 61, USA 180) | 06.11.2004 | CC SLC-17B | Delta-7925 | ||
GPS-2RM 1 (Navstar 53, USA 183) (ex GPS-2R 14) | 26.09.2005 | CC SLC-17A | Delta-7925 | ||
GPS-2RM 2 (Navstar 52, USA 190) (ex GPS-2R 15) | 25.09.2006 | CC SLC-17A | Delta-7925 | ||
GPS-2RM 3 (Navstar 58, USA 192) (ex GPS-2R 16) | 17.11.2006 | CC SLC-17 | Delta-7925 | ||
GPS-2RM 4 (Navstar 55, USA 196) (ex GPS-2R 17) | 17.10.2007 | CC SLC-17 | Delta-7925 | ||
GPS-2RM 5 (Navstar 57, USA 199) (ex GPS-2R 18) | 20.12.2007 | CC SLC-17 | Delta-7925 | ||
GPS-2RM 6 (Navstar 48, USA 201) (ex GPS-2R 19) | 15.03.2008 | CC SLC-17 | Delta-7925 | ||
GPS-2RM 7 (Navstar 49, USA 203) (ex GPS-2R 20) | 24.03.2009 | CC SLC-17A | Delta-7925 | ||
GPS-2RM 8 (Navstar 50, USA 206) (ex GPS-2R 21) | 17.08.2009 | CC SLC-17A | Delta-7925 | ||
GPS-2F 1 (Navstar 62, USA 213, Polaris) | 28.05.2010 | CC SLC-37B | Delta-4M+(4,2) | ||
GPS-2F 2 (Navstar 63, USA 231, Sirius) | 16.07.2011 | CC SLC-37B | Delta-4M+(4,2) | ||
GPS-2F 3 (Navstar 65, USA 239, Arcturus) | 04.10.2012 | CC SLC-37B | Delta-4M+(4,2) | ||
GPS-2F 4 (Navstar 66, USA 242, Vega) | 15.05.2013 | CC SLC-41 | Atlas-5(401) | ||
GPS-2F 5 (Navstar 64, USA 248, Canopus) | 21.02.2014 | CC SLC-37B | Delta-4M+(4,2) | ||
GPS-2F 6 (Navstar 67, USA 251, Rigel) | 17.05.2014 | CC SLC-37B | Delta-4M+(4,2) | ||
GPS-2F 7 (Navstar 68, USA 256, Capella) | 02.08.2014 | CC SLC-41 | Atlas-5(401) | ||
GPS-2F 8 (Navstar 69, USA 258, Spica) | 29.10.2014 | CC SLC-41 | Atlas-5(401) | ||
GPS-2F 9 (Navstar 71, USA 260, Deneb) | 25.03.2015 | CC SLC-37B | Delta-4M+(4,2) | ||
GPS-2F 10 (Navstar 72, USA 262, Antares) | 15.07.2015 | CC SLC-41 | Atlas-5(401) | ||
GPS-2F 11 (Navstar 73, USA 265, Altair) | 31.10.2015 | CC SLC-41 | Atlas-5(401) | ||
GPS-2F 12 (Navstar 70, USA 266, Betelgeuse) | 05.02.2016 | CC SLC-41 | Atlas-5(401) | ||
GPS-3 1 (Navstar 74, USA 289, Vespucci) | 23.12.2018 | CC SLC-40 | Falcon-9 v1.2 (Block 5)(ex) | ||
GPS-3 2 (Navstar 75, USA 293, Magellan) | 22.08.2019 | CC SLC-37B | Delta-4M+(4,2) (upg.) | ||
GPS-3 3 (Navstar 76, USA 304, Matthew Hensen) (ex Columbus) | 30.06.2020 | CC SLC-40 | Falcon-9 v1.2 (Block 5) | ||
GPS-3 4 (Navstar 77, USA 309, Sacagawea) | 05.11.2020 | CC SLC-40 | Falcon-9 v1.2 (Block 5) | ||
GPS-3 5 (Navstar 78, USA 319, Neil Armstrong) | 17.06.2021 | CC SLC-40 | Falcon-9 v1.2 (Block 5) | ||
GPS-3 6 (Navstar xx, Amelia Earhart) | 2022 | CC | Falcon-9 v1.2 (Block 5) | ||
GPS-3 7 (Navstar xx, Sally Ride) | 202x | CC | Vulcan Centaur VC0S | ||
GPS-3 8 (Navstar xx, Katherine Johnson) | 202x | CC | EELV-M (Vulcan Centaur VC0S or Falcon-9 v1.2 (Block 5) | ||
GPS-3 9 | 202x | CC | EELV-M (Vulcan Centaur VC0S or Falcon-9 v1.2 (Block 5) | ||
GPS-3 10 | 202x | CC | EELV-M (Vulcan Centaur VC0S or Falcon-9 v1.2 (Block 5) | ||
GPS-3F 1 (Navstar xx) | 2026 | CC | |||
GPS-3F 2 (Navstar xx) | 202x | CC | |||
GPS-3F 3 (Navstar xx) | 202x | CC | |||
GPS-3F 4 (Navstar xx) | 202x | CC | |||
GPS-3F 5 (Navstar xx) | 202x | CC | |||
GPS-3F 6 (Navstar xx) | 202x | CC | |||
GPS-3F 7 (Navstar xx) | 202x | CC | |||
GPS-3F 8 (Navstar xx) | 202x | CC | |||
GPS-3F 9 (Navstar xx) | 202x | CC | |||
GPS-3F 10 (Navstar xx) | 202x | CC | |||
GPS-3F 11 (Navstar xx) | 202x | CC | |||
GPS-3F 12 (Navstar xx) | 202x | CC | |||
GPS-3F 13 (Navstar xx) | 202x | CC | |||
GPS-3F 14 (Navstar xx) | 202x | CC | |||
GPS-3F 15 (Navstar xx) | 202x | CC | |||
GPS-3F 16 (Navstar xx) | 202x | CC | |||
GPS-3F 17 (Navstar xx) | 202x | CC | |||
GPS-3F 18 (Navstar xx) | 202x | CC | |||
GPS-3F 19 (Navstar xx) | 202x | CC | |||
GPS-3F 20 (Navstar xx) | 202x | CC | |||
GPS-3F 21 (Navstar xx) | 202x | CC | |||
GPS-3F 22 (Navstar xx) | 202x | CC |