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GNSS Constellations and Frequencies

Constellations

GPS
Center Frequencies (UHF) L1 (1575.42MHz), L2 (1227.60MHz), L5 (1176.45MHz)
Number of Satellites Baseline 24 satellites in 6 equally-spaced orbital planes for full coverage (in practice, 31 satellites)
Orbit MEO. 4 satellites per orbital plane, 26,560 km from the center of the Earth (about 20,200 km above the surface)
Satellite Types
  1. 7 Block IIR (Replenishment)
  2. 7 Block IIRM (Modernized)
  3. 12 Block IIF (Follow on)
  4. 4 Block III

Frequencies

GPS Frequencies

Carrier Band L1 L2 L3 L4 L5
Center Frequency 1575.42MHz 1227.60MHz 1381.05MHz 1379.91MHz 1176.45MHz
Carrier Wavelength (\(c / f_0\)) 19cm 24cm 25cm
Quadrature I/Q I/Q I/Q I/Q I/Q
Legacy Usage C/A, P(Y) P(Y)
Modern Usage C/A, P(Y), M, L1CD, L1CP P(Y), M, L2C I5-code, Q5-code