EKF and UKF algorithms and the application to terrain-aided navigation

Terrain-aided navigation technology corrects the inertial navigation error based on the terrains features. However, it is a nonlinear problem. EKF (Extended Kalman Filter) and UKF (Unscented Kalman Filter) could be employed to estimate and compensate the navigation error continuously. This paper analyzes the navigation performance of these two methods by comparing their simulation results. The results illustrate that the performance of UKF is better than EKF on the higher precision, less limitation to terrain, requirement of low sampling rate. If the dimension of state vector isn't so high, UKF is more feasible to the technical application.