Research on multipath error detection technology based on BDS three-frequency SNR

Multipath error is the distance error of receiver and star caused by the destructive interference of indirect waves on direct waves. The multipath effect has timevarying characteristics, Which is difficult to be eliminated by model correction or differential techniques. In the case of multipath interference, the signaltonoise ratio fluctuates at different frequencies of the same satellite fluctuates. Therefore, this paper proposes a method to detect multipath by SNR, which establishes a statistic about the signal-to-noise ratio (experimental environment) and calculates the detection threshold of the open environment (low multipath environment), and compareds the statistical values of the experimental environment with the values of the low multipath environment detection threshold to detect the multipath error of the BDS satellite. The experimental results show that the proposed method can effectively detect the multipath error of the BDS satellite, and obtain better positioning effect by remove the satellites in a certain period of time based on the detection threshold and the change of position dilution of precision(PDOP).