Single-epoch Compass Carrier-phase Ambiguous Resolution Using Three Civil Frequencies and Special Constellations

摘要

Tremendous research efforts have been made towardscarrier phase ambiguity resolution (AR) and positionestimation using three or more GNSS signals over thepast decade. With Compass/BeiDou-2 system, there arethree frequency bands available, one of which is onlyused for Authorized Service. Many people overlook aproblem. Compass system is the combination of RadioNavigation Satellite Service (RNSS) and RadioDetermination Satellite Service (RDSS). RDSS provide athird civil frequency for Compass system, which allowCompass to choose three frequencies for high-precisionnavigation. But the third civil frequency only exist on theGeostationary Orbit (GEO) Satellites. And RDSS signaltransmission is different from RNSS signals. There exitstill some problems and limitations when these methodsare used directly.A new technique for Compass carrier-phase single-epochambiguity resolution for short baseline is described in thispaper. The Compass combined RDSS+RNSS differentialcarrier-phase positioning method is first proposed. Then amodified TCAR method on three Compass civilfrequencies was used. Specifically, it uses a twodimensionalpositioning method to achieve accurate ARfor GEO satellites. Based on these, it then use the integerleast-squares (ILS) search method in one-dimensionalposition domain to obtain an accurate AR for Non-GEOsatellites. Test results show that, if baseline distance isless than 20km, the single epoch AR can be achieved withhigh success rate (>99.8%).