Presentation in ION GNSS+ 2023
Date:
Global Navigation Satellite System (GNSS) plays a crucial role in modern navigation systems, but its effectiveness is significantly challenged in urban environments due to the non-line-of-sight (NLOS) signal caused by reflection. In this paper, to essentially alleviate the NLOS problem, we propose an accurate NLOS correction method by Doppler-aided direction-of-arrival (DOA) estimation and 3D LiDAR-aided reflection restoration. For the first point, we propose a Doppler-aided optimization-based DOA estimation method that only requires receiver velocity. For the second point, we extend our conventional 3DLA GNSS to propose a 3D LiDAR-aided reflection restoration method including reflection point searching, correction formulation, and validation for reliable NLOS correction. Different from the conventional model-, or LiDAR-based NLOS correction methods, the proposed method does not rely on the shortest path assumption and therefore is able to correct NLOS receptions with errors exceeding 100 meters. The proposed method is evaluated using a representative urban canyon dataset and its effectiveness is proven by a nearly 80% average NLOS correction ratio and over 80% positioning accuracy improvement.