Research On The Test System Of Satellite Navigation Enhanced Terminal

To fulfill the applications of that navigation terminal should be highly reliable and qualified in various fields.Pure GNSS navigation system due to the regional influence,signals travel in the busy streets,buildings and other environmental vulnerable to keep out in the process,leading to the terminal unable to locate or poor positioning results.The wireless communication with the mobile network,WIFI signal may be effectively spread in the above environment,whereas the lower the positioning accuracy of its own.Therefore,study the integration of satellite navigation and wireless communications based positioning technology has become a hot technology,enhanced navigation terminal corresponding development widely used.To ensure the quality and reliability of various types of enhanced terminal,all aspects of its product development,test validation,production inspection,and so need a scientific,rational and efficient test system.However,existing domestic navigation terminal test system is aimed primarily satellite navigation terminal,unable to provide testing services to enhance navigation terminals.This paper focuses on the construction of simulation test systems for A-GNSS,SBAS and GNSS integrated with WIFI based on GNSS satellite signal simulator.The research work mainly includes the following aspects:First,research has been done on A-GNSS,SBAS and WIFI integration GNSS positioning technology.Among them,analysis of the A-GPS assisted positioning in how to use forecasting Doppler and other auxiliary data to improve efficiency of the terminal capturing navigation signals.The SBAS enhancing terminal positioning how to use ephemeris errors,clock errors and ionospheric delay error correction data improve positioning accuracy of the terminal.RSSI positioning algorithm in WIFI positioning technology and GNSS integrated with WIFI positioning algorithm.Second,this paper discusses how to construct a wireless communication integrated GNSS enhanced terminal simulation test system and the related technology in detail.Which was constructed A-GNSS simulation test system to solve the system auxiliary data generation computing and codec problem.Constructed of the SBAS simulation test system,and to solve the system of ephemeris error correction,clock error correction and ionospheric delay error correction simulation model problems.GNSS integrated with WIFI simulation test system is put forward,and Modeling and Simulation problem WIFI signal propagation model are studied.Third,research on test system GNSS satellite navigation signal simulator calibration technology,to ensure the accuracy and the credibility of the signals sent by the test system.Finally,an assessment of the key indicators for the test system has been proposed,including the first location time,location accuracy and so on,which has been validated using related experiments.This paper mainly focuses on the practical issues over wireless communication integrated GNSS terminal test system,and some of the achievements have been put into used.Therefore,the research for the Constructing and improving of fusion navigation terminal test system of our country has great significance in promoting.