GNSS and performance-based navigation
10 min read
GNSS
Satellites send their position and time; the receiver measures the range to each. Four satellites give a 3D position and the clock error. RAIM (receiver autonomous integrity monitoring) needs at least five to detect a faulty satellite, and six to also exclude it (FDE); barometric aiding can replace one satellite.
The biggest natural error is the ionospheric delay. SBAS (such as EGNOS in Europe and WAAS in the US) sends corrections and integrity information, allowing LPV approaches.
IN THIS LESSON
- PBN
- RNP APCH minima
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