Mitigating GNSS Multipath Effects Based on RHT Slope Mitigation and Adaptive Carrier Signal Tracking

Abstract

Starting from the traditional receiver loop multipath suppression method, the delay effect of multipath effect on receiver tracking and capture is mitrgated in parallel by correcting the code loop correlation curve distortion and adaptive carrier signal update mechanism to track the weak dynamic carrier signal at two levels. First, an adaptive threshold carrier tracking signal state model is designed to solve the problem of limited signal tracking under high occlusion and low CNR conditions, with the aid of the Random Hough Transform slope detection method in the field of machine learning to reduce the error of narrow correlator. Comparson was made with existing methods from different perspectives. The results show that the localization modeling property of applying the RHT method assisted by adaptive enhanced carrier signal tracking is significantly improved compared with both the conventional HRC and Kalman filter carrier tracking methods, with the method proposed in this paper being able to recover the carrier signal out of lock in time for a signal delay of around 1.8 s. In addition, the final localization results show that the root mean square error is reduced by 6.3 m in the D region of the experimental scenario where the MP effect is strong.

Keywords

• global navigation satellite system(gnss)
• multipath effects
• receiver tracking loop
• adaptive signal pattern
• rht slope mitigation