Ultra-tight integration of global position system, Pseudolites and inertial navigation system using Kalman filter

Abstract

The main driving force to integrate these two navigation systems as an integrated GPS/INS system in different architectural forms to provide robust positioning. The complementary advantages of GPS and INS have been extracted. The loosely coupled and tightly coupled GPS/INS systems have been in existence for more than two decades and performed reasonably well, nevertheless, the tracking performance was still a problem to be addressed in non-benign environments such as dynamic scenarios, indoor environments, urban areas, under foliages etc., where the GPS tracking loops lose lock due to the weak signals, subjected to excessive dynamics or completely blocked. The strong force for this research, therefore, was to address these limitations with ultra-tight integration architecture of GPS/Pseudolite/ INS system using Kalman filter. The main research contributions are written in brief: 1. The performance of the tracking loops in dynamic scenarios were analysed in detail with both conventional and ultra-tight software receivers. The stochastic modelling of the INS-derived Doppler is of the most important in improving the merits of ultra-tight integration, and therefore, two popular stochastic techniques Gauss Markov (GM) and Autoregressive (AR), were investigated to model the Doppler.The main driving force to integrate these two navigation systems as an integrated GPS/INS system in different architectural forms to provide robust positioning. The complementary advantages of GPS and INS have been extracted. The loosely coupled and tightly coupled GPS/INS systems have been in existence for more than two decades and performed reasonably well, nevertheless, the tracking performance was still a problem to be addressed in non-benign environments such as dynamic scenarios, indoor environments, urban areas, under foliages etc., where the GPS tracking loops lose lock due to the weak signals, subjected to excessive dynamics or completely blocked..