GPS/INS Integrated Navigation by Fading Filtering Based on Wavelet De-noising

The motion compensation of Global Navigation Satellite System (GNSS) and Micro-Electro-Mechanical Inertial Navigation System (MINS) can effectively correct and compensate the motion errors of the Synthetic Aperture Radar (SAR) platform. In this paper, firstly, the long-term errors of the MINS have been analyzed and modeled using the Allan variance method under the view of time-frequency analysis. Secondly, the short-term errors in the motion characteristic bands have been reduced by utilizing the wavelet thresholding de-noising method to decrease the effects of gross errors on the system. Finally, the preprocessed data solution via dead reckoning has been conducted by using fading filtering algorithm. The experimental results have indicated that the proposed approach effectively reduces the influence of the errors of the inertia devices, preferably eliminates the gross errors, recovers the data and improves the precision of the GNSS / MINS integrated navigation system in order to obtain high quality SAR images.