Research On Combined Satellite Selection Algorithm Of BDS And GPS And Analysis Of Positioning Performance

In the field of satellite navigation and positioning,GPS has been widely used.Meanwhile,Beidou satellite system(BDS)independently developed by China has been gradually improved.The multi-constellation technology can be used for the combined positioning of BDS and GPS to improve the positioning accuracy where satellite selection algorithm is a key technology.It has important theoretical significance and practical value to study the satellite selection algorithm.The paper introduces the composition and positioning process of BDS and GPS,and studied the time system unification,the coordinate system unification and the positioning solution principle of combined positioning of BDS and GPS.BDSim software was used to simulate BDS and GPS for analyzing the performance.The constellation optimization technology was studied.With the analysis of the traditional satellite selection algorithm,an improved satellite selection algorithm was presented on the basis of genetic algorithm.The generation of the initial population,genetic operation and algorithm flow were optimized.The simulation tool was designed and debugged to verify the result.Simulation results proved that the improved satellite selection algorithm could found the satellite combination of relatively small GDOP with low computational consumption and hardware configuration which could reduce the cost of the receiver.