A Autonomous Navigation Algorithm Based On The X-ray Pulsars

Autonomous navigation refers to a system which only uses onboard observation equipments to determine its own position and speed, but not relying on ground facilities. Pulsar navigation is one of the astronomy autonomous navigation, and it's a new direction of autonomous navigation research. Pulsar is a kind of neutron star with super strong electro-magnetic field and super density. It spins rapidly and extremely stably. Its long-term stability could even be better than the best atomic clock in the world. And the high accuracy time standard is the core of all kind of navigation system. Because of this great characteristic, pulsar gets people to notice its huge potential to keep time and navigate. But for the complexity of the new method and system, at present, the study of pulsar navigation is still on the stage of theoretical study. Especially in China, the research is just starting up.Based on the similarity of the GPS navigation, this dissertation studies and analyzes the method of pulsar navigation as an exploratory theoretical study. This dissertation presents the method of observing X-ray photon and the creation of standard pulse profile as well as the creation of timing model. In this dissertation, the study focuses on the method of absolute position determination using the error of the time of arrival and the predicted time. The theory of this navigation method is deeply analyzed and the algorithm is carefully derived. In the end, a navigation simulation using MATLAB is built for the position determination method. The result shows that the position precision improves with the clock precision and phase precision.