Researches And Implements On Orientation Algorithm Based On Beidou-2 Navigation System

Satellite orientation algorithm is the key component of satellite navigation system,which is a research hotspot in the field of satellite technology in recent years.The inaccurate satellite orientation results are caused by the large amount of observation data,susceptible satellite observations and unreasonable search strategies etc,and they affect the further development of the satellite technology.So it has theoretical and practical significance to research the more fast and efficient orientation algorithm.On the basis of the basic framework of Beidou-2 Navigation Satellite System,the paper studies on orientation algorithm,as well as two core technologies:Cycle slip detection and repair algorithm and ambiguity estimation algorithm.According to Cycle slip detection and repair algorithm:through realizing carrier phase rate algorithm,a method of combining carrier phase rate and redundant double difference algorithm is proposed.On the basis of the retention of short time,the method can effectively detect and repair the small-scale cycle slip by weakening the noise.And the algorithm can effectively improve the orientation accuracy.According to ambiguity estimation algorithm:through realizing Least-Square algorithm,Recursive Least Square is brought in.The algorithm considers that current estimated values have already contained all the information before,not all observations are needed to be saved,and a set of carrier phase observation data can estimate parameters at a time.Only the current observation is needed,which not only ensures the estimation precision,but also reduces the computational complexity.The algorithm designed is simulated and verified by experiments.And the experimental results show that the method of combining carrier phase rate and redundant double difference algorithm for cycle slip detection and repair not only can determine the epoch that has cycle slips,but also effectively detect and repair the small-scale cycle slip.The algorithm robustness is improved.The use of Recursive Least Square to ambiguity estimation can remain high success rate,as well as can reduce orientation time.And the real-time performance of algorithm is improved.