Application of wavelet threshold filter in initial alignment of SINS for land vehicle

In order to improve accuracy and convergence rate of alignment of SINS for land vehicle, with considering the SINS error model and analyzing the major noise sources, the wavelet threshold filter was applied to eliminate high frequency noise in signal effectively. Next, initial alignment was by completed adaptive Kalman filter to reduce the errors from the inaccurate mathematical models and statistical properties of noise. Finally, the experiment results show the methods with wavelet threshold filter and adaptive Kalman filter improve effectively the convergence rate and alignment accuracy. It can satisfy the demands of navigation for land vehicle in general environment, and has a greater practical engineering value.