The Research On Beidou Location Arithmetic And Its Application In Embedded Navigator

Beidou Navigation Satellite System is regional satellite positioning system, and it is independent designed and R&D by china. Beidou Navigation System can cover only china, it has been gradually applied to varous fields such as mapping, water conservancy, transportation, exploration and military fields since2000. Beidou Navigation System is playing an increasingly important role. In practice, the position error of Beidou Navigation System is relatively big and there are gaps between coordinate location and the actual location. So it is necessary to optimize location algorithm and process location datas in order to improve precision.Because of the issues that location error is bigger and it is difficult to correctly match satellite positioning data with map data. After a detailed and in-depth research on related positioning algorithms of Beidou System and map matching methods, this thesis puts forward the corresponding strategy, not only can it reduce the positioning error but also it can make satellite positioning data match with the map correctly. This thesis studies several aspects as follows:1. In order to reduce the positioning error this thesis uses the pseudolite technology to carry on the optimization to the satellite layout. Firstly this thesis discusses the situation with only one pseudolite, and the singular points appear in this situation, moreover the pseudolite position request to be strict. This thesis uses two pseudolites to carry on the localization and imporve the localization error finally.2. Between map coordinates and actual geography latitude and longitude existence disparity, so the data obtained by the first step need to be disposed. This thesis propose a synthetic matching algorithm after doing a thorough research on others matching algorithm. This algorithm uses threshold and matching degree constraints and union map topology to match the points to the roads. This thesis combines the matched data and wireless transmission technology to a system and realizes the optimization of urban roads and vehicles’s dispatch finally. The experimental results show that the improved matching algoritm can match the roads on the map correctly.