Multipath Mitigation using GPS/INS Integrated Navigation with Adaptive Kalman Filtering

In urban canyon, the multipath errors are significant and the number of usable satellites frequently lacks. In this paper, to overcome these problems, the GPS/INS integrated navigation algorithm is used. For the absolute position measurement, the code-based GPS position is used with suitable measurement noise covariance tuning in adaptive way because the general GPS/INS integrated navigation suffers from the significant multipath error. To achieve effective mitigation of multipath error, we first analyzed the characteristics of the multipath error in urban canyon. Then based on the observation, we can effectively mitigate the multipath error in GPS/INS integrated navigation using adaptive measurement noise covariance tuning. It is important because the Kalman filter can guarantee the optimal performance when the noise covariance were properly decided. As a result, above 30% improvement of positioning accuracy was achieved.