Multi-Epoch Kriging-Based 3D Mapping-Aided GNSS and Doppler Measurement Fusion using Factor Graph Optimization

Abstract

Navigation and positioning are integral activities in the current society, and global navigation satellite systems (GNSSs) are widely used to perform globally referenced positioning. However, the performance of GNSSs in urban positioning is often unsatisfactory. The poor performance occurs because a GNSS signal does not travel in a line-of-sight (LOS) route directly to the receiver in such scenarios but is reflected or attenuated over buildings and obstacles. Signal propagation errors, such as non-LOS (NLOS), multipath, and diffraction reception errors, for GNSS signals deteriorate the positioning performance (Groves, 2013a). Moreover, the reflected signal experiences an additional time delay and must travel further, leading to the generation of positioning errors exceeding 50 m. Nevertheless, GNSS methods must be implemented in locations with tall buildings to provide absolute coordinates in the global frame for location-based services (LBSs). Therefore,