Navigation Domain Multipath Characterization Using GNSS Direct Position Estimation in Urban Canyon Environment

Abstract

Multipath is a common factor that degrade the performance of Global Navigation Satellite System (GNSS), especially in urban canyon and indoor environments. Due to the reflection of surrounding buildings, multiple Non-Line of Sight (NLOS) signals will arrive receiver antenna with various paths, and the Line of Sight (LOS) signals parameters such as the amplitude and phase will suffer significant distortions and fluctuation. However, due to the random feature of temporal, spatial and frequency diversity across the signal bands, it is difficult to accurately characterize the multipath effect. In this paper, a new attempt has been made to characterize the multipath fading in navigation domain using GNSS direct position estimation (DPE) algorithm. Live tests were conducted in viaduct and urban environments in Shanghai with both traditional two-step and DPE algorithm. The results show the robust of DPE no matter the receiver is moving or static. And the navigation domain manifolds for viaduct and urban scenarios are compared to characterize the multipath fading. The results demonstrate the feasibility of navigation domain multipath characterization using GNSS direct position estimation in urban canyon environment.