Analysis on BDS Satellite-Induced Multipath and Its Impact on Time Transfer

摘要

There are systematic multipath errors on BeiDou code measurements, ranging from several decimeters to more than 1 m. The impact of BDS satellite-induced multipath on time transfer was comprehensively analyzed. Firstly, the piecewise liner correction model was constructed using the observation data collected from 17 MGEX stations over a time span of 30 days. Secondly, the time transfer results of 4 time labs located in Europe-Asia were analyzed in different time transfer mode, including single-station BDS CV (common view), two-station BDS CV, single-station BDS PPP (precise point positioning) and two-station BDS PPP. Experiments show that the systematic error originated from the satellite-induced multipath is about 0.5 ns-1.0 ns when time transferring in Asia or Europe. The maximum error are 3 ns-4 ns for single satellite BDS CV. The error will be obviously canceled when time transferring in short baseline, but not for long baseline, which is up to 1.5 ns and must be corrected.