摘要
地球静止轨道GEO卫星定轨是精密定轨领域的难点。依托我国区域范围地面跟踪网实际,提出了转发式测距数据支持下的GEO导航卫星精密定轨方案。从定轨精度、设备时延和伪距站对GEO轨道精度影响等方面进行了深入分析。试验结果证明:1ns的时延误差引进的GEO轨道径向和位置误差分别为0.121m和3.505m。在多个转发式测距跟踪站约束的条件下伪距对定轨精度贡献非常有限,但通过星地钟差的估计可以实现时间同步,同步精度优于1ns。这为时间同步提供了一种新的方法。当转发式测距跟踪站有限时伪距对GEO定轨的贡献非常明显,1CC(转发式跟踪站)+7L(伪距站)联合定轨条件下的轨道精度优于5m。从而解决了GEO卫星精密定轨问题,同时实现了星地和站间时间同步以及卫星轨道与钟差参数的自洽。
Precise orbit determination of GEO satellite is a problem. A new method of GEO orbit determination based on pseudo-range observation and transfer ranging data was proposed. The ranging models of two types of data were analyzed and the principle of orbit determination was deduced. Based on the simulation experiments of the local area of China, several influences to GEO orbit determination accuracy were analyzed including orbit determination accuracy, equipment time-delay and pseudo-range sites. According to the experiments, the radical errors and position errors caused by 1 ns time-delay were respectively 0. 121 m and 3. 505 m. The contribution of pseudo-range observation to orbit determination was limited with the restriction of several transfer ranging sites. Through the estimation of satellite-to-site clock error which provided a new solution of time synchronization, time synchronization was realized and the accuracy is prior to 1 ns. The contribution of pseudorange observation to orbit determination was effective when the transfer ranging site was insufficient. The orbit accuracy was prior to 5 m on the condition of 1CC＋ 7L combination orbit determination, which not only obtained a solution of GEO orbit determination but also realized the satellite-to-site time synchronization and site-to site time synchronization, while achieved inner consistent between satellite orbit and clock parameters.
出处
《测绘科学技术学报》
北大核心
2010年第5期332-336,共5页
Journal of Geomatics Science and Technology
基金
国家863计划课题资助项目(2007AA12Z345)
上海空间导航与定位技术重点实验室资助项目(06DZ22101)
武汉大学卫星导航与定位教育部重点实验室资助项目(GRC-2009004)
关键词
精密定轨
伪距
转发式测距
地球静止轨道
导航卫星
precise orbit determination
pseudo-range observation
transfer ranging
GEO
navigation satellite
