The Soacecraft Positioning Method Based On Fusion Of Pulsar Vector And Timing Observation

The traditional X-ray Pulsar Navigation only uses timing observation of pulsar radiation as its input information, which will result in under-utilization of pulsar navigation capacity and low accuracy of positioning. The thesis proposes an autonomous navigation method based on the fusion of pulsar vector observation and timing observation, which will make full use of pulsar navigation ability and improve the positioning accuracy.Firstly, the geometric model of X-ray detector equipped with collimator is introduced, on which basis the detector's effective area is formulated. Simultaneously, in order to obtain the position vector, a position vector searching strategy is proposed, which uses X-ray photon flux intensity as its objective function. Then the integrated observation model is established on the basis of the fusion of position vector observation together with timing observation. With the combination of EKF algorithm and orbital dynamics equation of spacecrafts, the integrated Kalman Filtering and Federated Kalman Filtering are designed. Finally, simulation results show that the vector searching method is feasible. And compared with the methods only using vector observation or timing observation, the method based on the fusion of pulsar vector observation and timing observation can obviously improve the positioning accuracy of X-ray Pulsar Navigation.