CODE新光压模型对北斗混合导航星座精密轨道确定的影响

摘要

The performance of CODE′s new solar radiation pressure model, the EECOM(extended empirical CODE orbit model), was analyzed on precise orbit determination for mixed-type BeiDou constellation.This study is based on the NUDTTK software,which is a satellite orbit determination toolkit.The validation of satellite laser ranging reveals that the EECOM can improve orbital accuracy of geostationary earth orbit satellites by 17.4% and 35.1%, compared with traditional CODE′s ECOM-9 and ECOM-5 models, respectively.As to the inclined geosynchronous earth orbit and the medium earth orbit satellites, the ECOM-5 model performs better than EECOM as well as ECOM-9 model.It means that CODE′s new solar radiation pressure model is not able to improve the orbital accuracy of the inclined geosynchronous earth orbit and the medium earth orbit satellites.External orbit validation by IGS data analysis centers of GFZ, WHU and CODE indicates that the accuracy of our current BeiDou precision orbit is 1~4 m for geostationary earth orbit satellites,25 ~30 cm for inclined geosynchronous earth orbit satellites and 10~20 cm for medium earth orbit satellites, respectively.%运用卫星定轨软件工具包NUDTTK,分析了欧洲定轨中心扩展的经验光压模型(EECOM)对北斗二代混合导航星座精密轨道确定的影响.研究表明:对地球静止轨道卫星而言,EECOM能够明显改善定轨精度,相比于传统的ECOM-9和ECOM-5模型,卫星激光测距检核精度分别提高17.4%和35.1%.对倾斜地球同步轨道卫星和中轨道卫星而言,采用ECOM-5模型的定轨精度要优于采用EECOM和ECOM-9模型的,新光压模型EECOM并不能有效改善倾斜地球同步轨道卫星和中轨道卫星的定轨精度.与IGS数据分析中心WHU、GFZ和CODE的轨道产品相互比对的结果显示:目前,国防科技大学北斗精密轨道产品中,地球静止轨道卫星的定轨精度为1~4 m,倾斜地球同步轨道卫星的定轨精度为25~30 cm,中轨道卫星的定轨精度为10~20 cm.