应用扩展卡尔曼滤波平滑算法提高GPS/INS组合定位定姿精度

In this paper, extended Kalman filter and R-T-S smoothing algorithm have been studied in order to improve GPS/INS integrated position and attitude accuracy in the case that GPS fails to position independently for a long time due to occlusion in the city, meanwhile, GPS/INS integrated system state equation based on INS error model and measurement equation based on position, speed update have been put forward. In the experiment, GPS outage for 60 seconds is simulated and GPS/INS integrated data are processed with R-T-S post processing algorithm. The experiment shows that extended Kalman smoothing algorithm can efficiently improve GPS/INS integrated positioning and attitude accuracy under the circumstance of occlusion in the city, especially in the case of GPS outage, thus reducing dependence on costly INS to a great extent.