Abstract:

The multipath mitigation and unambiguous tracking for modulated signals are two important requirements of the code tracking loop in modern global navigation satellite system （GNSS） receivers. A code discriminator design method based on optimization technique is proposed to meet these requirements. The proposed discriminator is based on multicorrelator structure and the combined weights are treated as optimization variable. The mathematical constraints are given according to the unambiguous tracking requirement, and the enclose area of multipath error envelope is used as an objective function to establish the optimization problem. Then an initial value setting method based on curve shaping technique is proposed. The simulation results indicate that compared with the traditional discriminator the proposed discriminator performs better in multipath mitigation and it can track binary offset carrier modulated signals unambiguously.