Abstract:In order to solve the nonlinear system filtering problem in X-ray pulsar based autonomous navigation, the unscented Kalman filter (UKF) method is applied in autonomous navigation calculation. Firstly, the feasibility of Pulsar based navigation is briefly introduced, and the basic principle and implementation scheme of the Pulsar based autonomous navigation system are studied. Then, based on the Newtonian two-body gravitational model, the motion state equation of the spacecraft is constructed, the systematic observation equation is established based on the pulse time of arrival (TOA) model, and the error analysis and modeling are carried out. Finally, the UKF algorithm is applied in the process of spacecraft autonomous navigation, and the simulation results show that this method can realize the calculation of spacecraft autonomous navigation information.