Performance analysis of multipath mitigation for BOC modulated signals based on multiple gate delay structure

Multipath interferences are difficult to eliminate through the differential method because they are not interrelated in space, multipath is one of the most dominant sources of errors in global navigation satellite systems (GNSS). In this paper, the multiple gate delay (MGD) method employs 3 pairs of correlators which are located in uniform space mode. The MGD early-late gate coefficients are optimized by minimizing the areas closed by the weighted and nonweighted multipath error envelopes under limited bandwidth. Binary offset carrier (BOC) modulations have been warmly recommended in the GNSS for some advantages. The classic signals Sine-phased BOC (SinBOC) and the alternative BOC (AltBOC) were chosen as examples, and the performances of the MGD method were compared with traditional narrow correlator (NC) method and the high-resolution correlator (HRC) method. The results show that the area closed by the multipath error envelopes of MGD method is smaller than those of NC and HRC methods, and the MGD method is better than NC and HRC methods at mitigating the short-delayed multipath.