A New Method Of Star Selection For Beidou Satellite Based On Non-negative Matrix Blind Decomposition

Global Navigation Satellite System(GNSS)is widely used in social life,production and economic activities,such as intelligent transportation,Internet,mobile communications,hydrological mapping and other industries.Therefore,many countries have invested a lot of manpower and material resources to carry out independent satellite navigation system modernization research.Considering the safety of the country and the people,and in order to meet the needs of economic and social development,China has independently developed Beidou satellite navigation system,which is an independent global satellite navigation system.At present,the global satellite navigation system continues to develop and improve.With the increasing number of visible satellites captured,too much redundant information captured will not only not improve the positioning accuracy of the satellite,but also increase the calculation amount of navigation solution,which seriously affects the real-time performance of navigation and positioning,and also increases the difficulty and cost of the hardware design of the multi system receiver in engineering.In addition,in some cases In severe extreme environment,such as remote mountainous areas with poor signal reception,cities with high buildings and other obstructions,the receiver may receive weak signals.Therefore,how to select the appropriate satellite navigation combination from the captured visible satellites so that the navigation system can ensure the positioning accuracy while having good real-time performance is a very important thing.In this paper,the method of satellite selection for Beidou satellite navigation system is studied in the harsh environment with occlusion.By improving the algorithm of satellite selection,the accuracy of satellite positioning in the harsh environment is optimized and the calculation of positioning solution is reduced.The research content of this paper mainly includes the following three aspects:1,This paper studies the calculation principle and steps of the star selection algorithm of Beidou satellite navigation system,analyzes the main parameters affecting the satellite positioning accuracy,and lays a theoretical foundation for the following new star selection method of Beidou satellite to improve the satellite positioning accuracy in harsh environment.2,This paper studies the composition and characteristics of Beidou satellite signal,proposes to build an improved Beidou satellite selection model to strengthen the sign al strength weight,uses the carrier signal of the satellite as the strength amplitude,con structs a new orientation and strength matrix,to a certain extent,solves the problem th at the signal of the satellite receiver is weak and cannot be accurately located in the harsh environment.3,This paper studies the advantages and feasibility of non-negative matrix algorit hm.Based on the traditional star selection algorithm of Beidou satellite,a new star sel ection method based on non-negative matrix blind decomposition is proposed.The non-negative matrix algorithm is used to solve the matrix of azimuth and strength,which not only improves the positioning accuracy of the satellite,but also reduces the calcul ation amount of positioning solution.In this paper,MATLAB software is used to simulate and verify the method proposed in this paper.Two sets of simulation data are used,which are the data information of eight Beidou satellites in common environment and bad environment.The simulation results show that the model algorithm proposed in this paper is feasible and effective,and overcomes the problem of low positioning accuracy in bad environment with obstructions.Compared with the traditional satellite selection algorithm The algorithm of this paper can greatly reduce the amount of computation and improve the real-time performance of positioning,which has good academic research value and application prospects.