Research On Integrity Monitoring Technology For SBAS Based On BDS

With the rapid development and modernization of satellite navigation technology, the positioning precision of users has been greatly improved. Satellite navigation still cannot be used as the main aviation navigation system in all flight phase though it has been widely used, for the integrity cannot fit the request of its users. From the perspective of user safety, integrity is more vital than precision. Thus augmentation systems for GPS and GLONASS were emerged.SBAS monitor satellite signal by monitor stations, then send the information which was processed for the purpose of integrity to users. And Users correct positioning result by the information. This paper studied SBAS integrity monitor technology base on BDS. The main contents as follows:1. The background and status of research at home and abroad of this topic are briefly introduced, and then the current global satellite navigation system and SBAS are discussed.2. The structure and theory of WAAS and Galileo are introduced, the integrity parameters include SISE?SISA?SISMA and IF on Galileo are analyzed. The parameter algorithm for integrity include UDRE and GIVE on WAAS are researched and simulated. On the basis, SBAS integrity monitoring technology and parameters based on BDS are introduced. The similarities and differences in integrity monitoring between BDS, WAAS and Galileo are contrasted and analyzed.3.The main error resource of BDS are introduced, the parameters for integrity include UDRE, RURA and GIVE on BDS are analyzed. The variations of the UDRE and RURA in a whole day are simulated and analyzed, the value of UDRE and RURA is in the range of integrity monitoring, and the algorithm of UDRE and RURA are verified. In addition, the variation of the GIVE regarding IGP and UIVE in a whole day is presented.The simulation shows that the algorithms of GIVE can limit the grid point ionospheric delay error with a confidence level of 99.9%.4.The function and important role in integrity monitoring of monitor stations are introduced, the rule of monitor stations distribution is researched. Considering the characteristic of BDS, the monitor stations distributing proposal in China is presented.