Satellite-Induced Multipath Analysis on the Cause of BeiDou Code Pseudorange Bias

摘要

Data from previous observation have shown that the BeiDou satellite navigation system (BDS) has been suffering from satellite-induced elevation-dependent code pseudorange bias, which can be as much as 1 m and degrade the performance of high-precision applications such as Precise Point Positioning (PPP). Mechanism analysis on the cause of the bias has been absent in previous literature, which is essential to avoid the issue from happening again in following satellites. In this paper, both theoretical analyses and simulations are performed, proving that the bias can be caused by the multipath effect induced by the transmitting array on the satellite. Based on a proper model of this satellite-induced multipath effect, the bias values can be calculated through mathematical derivation. Under certain model parameters, the simulation results agree with the observed bias values very well. Methods and conclusions of this paper are useful in both investigating the current BeiDou bias issue and the process of design, development and test of following satellites by satellite manufactures.