Research On The Nonlinear Filtering Algorithm In The Integrated Navigation Systen Of Beidou/INS

BeiDou Navigation Satellite System (BDS) is a global satellite navigation system which is being implemented in China. To build the BeiDou Navigation Satellite System to build an independent, technologically advanced, opened and compatible, stable and reliable coverage of the global navigation and positioning system is to promote the formation of China’s satellite navigation industry chain, and the formation of a sound national satellite navigation application industry support, promotion and protection system, and promote the satellite navigation in the national economic and social sectors of the wide range of applications. The combination of Beidou satellite navigation system and inertial navigation system is very important to realize the integrated navigation and positioning system in China. In this paper, the nonlinear filtering algorithm for the integrated navigation system based on/INS is studied and analyzed in this paper.1.This paper firstly analyzes the combination Beidou/INS Integrated Navigation System,Comparative advantages and disadvantages of the two navigation methods. Then according to the integrated navigation method listed the state equation and the measurement equation. Finally, select the location and velocity information in combination pine navigation mode, using the indirect method, several nonlinear algorithm for application simulation.2.Research the unscented Kalman filter algorithm, particle filter, unscented particle filter algorithm nonlinear algorithm, on the basis of these three algorithms for unscented particle filtering algorithm is improved. UT symmetry transformation from the sampling method to the proportion of symmetric sampling method for sampling, resampling algorithm in particle filter section, the system resampling method changed from general resampling method, Beidou/INS navigation system after improvement after filtering unscented particle filter, the system resampling method is not only good to improve the particle filter particle degradation, also increased the proportion of symmetric. Proportional symmetric sampling also improves the accuracy of the sampling points in the UT transform. Thereby improving the overall accuracy of the algorithm filtering, and better stability.3.In the MATLAB environment, simulated carrier’s flight, a run track. The position and velocity as navigation parameters, namely the four kinds of nonlinear filtering algorithm are applied to Beidou/INS integrated navigation system, to a filtering process. By a large number of simulation experiments it proved unscented particle filter algorithm after improvement, compared to several other nonlinear filtering algorithm has better filtering effect.