Multi-Fault Tolerant RAIM Algorithm for Hybrid GPS/TV Positioning

摘要

Terrestrial communication signals, such as television, cellular and wireless LAN signals, have been pursued as ranging sources for deeper penetration into urban and indoor areas. However, because these signals are not designed for positioning and travel in severer multipath environments, there tend to be more outlying pseudorange measurements in terrestrial signal-based positioning systems than in space (satellite) signal-based positioning systems. The resulting multiplicity of outliers makes it more challenging for receiver autonomous integrity monitoring (RAIM) algorithms to provide reliable position estimates because conventional RAIM algorithms for satellite systems assume usually a single satellite failure. To handle this multi-fault case, we modify the three conventional RAIM algorithms–the chi-square test, the horizontal protection level test (HPL) and the multi-hypothesis solution separation test (MHSS)–with iterative fault detection and exclusion steps as well as the clusterization of transmitters, and compare their performance based on hybrid GPS and TV pseudorange measurements.