Multipath Suppression Performance Analysis of Multiple Gate Delay Structure for GNSS Signals

Multipath interferences which are difficult to be eliminated through the differential method because they are not interrelated in space,affects the positioning accuracy of global navigation satellite systems(GNSS). The navigation signals in the receiver are affected by the front-end bandwidth,and the close multipath interference suppression has more practical significance. From the two aspects a multipath interference suppression method based on multiple gate delay( MGD) is proposed in this paper. The multipath error mathematical expressions of the MGD method under limited bandwidth are derived,the early-late gate coefficients of the MGD are optimized by minimizing the areas closed by the weighted and non-weighted multipath error envelopes,and the typical navigation signal SinBOC(10,5) is chosen as an example to illustrate the performance of the method. The results show that for SinBOC(10,5) the area closed by the multipath error envelopes of MGD method is less than that of the high-resolution correlator(HRC)method at least 15%,and when the front-end bandwidth is large,for the small and medium delayed multipath signal the multipath error of the MGD method is less than that of HRC method.