基于基线延长的高精度北斗双星系统快速定向算法研究

Fast Orientation Determination with High Precision by Beidou Twin-Star System Based on Extended Baseline

由于北斗定位系统的两颗卫星位于赤道的同步轨道,对地静止且可观测的载波相位信息少,因此传统多星系统求解整周模糊度进行定向的方法难以直接利用。针对此情况,利用延长基线可改变卫星-天线几何关系的方法,求解载波相位的整周模糊度,化不利为有利,实现双星的快速定向。针对基线在不同区域不同姿态下的仿真表明:当测试条件为基线原长1.5m,延长倍数为4时,载波相位测量精度为1%周,可实现优于0.1°的方位精度和0.05°的俯仰精度,如果延长基线或增加延长倍数,还可取得更高精度,证实了该方法的可行性和高精度性。同时由于该方法的基线安装机构简单可靠,使用时便于展开,因此可应用于环境复杂的快速定向场合。

Because double stars of Beidou system are stationary sateUites and have no redundant measurement information, it is difficult to determine orientation through the usual ambiguity resolutions of multi-satellite system. To this question a new ambiguity resolution is proposed . This method adopts the feature that extended baseline can change the geometric relationship between sat- ellites and antennas. And through the extended baseline the orientation determination is fast and convenient. The project has been simulated in various conditions. The result shows that the accuracy of 0.1° for yaw and 0.05° for pitch can be reached with a 1. 5m baseline, 4 multiple and the accuracy of 1% cycle for phase measurement. With the longer baseline and the greater multiple, the precision can be higher. At the same time the structure of the extended baseline is reliable, and easy to be assembled and operated quickly. So it can be used in the complex environment for the fast orientation determination.