轨位偏置的GEO卫星轨道快速恢复技术

Research on technique of orbit rapid recovery for GEO satellite of partial subsatellite point

北斗系统中轨位资源相对匮乏的GEO卫星需要频繁轨控来保持轨位,其轨控后的轨道快速恢复问题,是制约卫星可用度和系统服务性能的重要因素.GEO卫星静地特性使得难以实现轨道参数与钟参数的有效分离,特别针对轨位偏置GEO卫星该问题更加突出.本文提出了星地钟差支持下的轨道快速恢复技术,通过无线电双向法实现星地时间同步和多星定轨实现高精度站间时间同步,实现了钟差与轨道的有效分离.本文同时提出具有先验约束的降相关方法和基于长弧约束短弧运动学和动力学参数的轨道快速恢复方法,有效解决了监测接收机系统差问题,实现了高精度的轨道快速恢复.基于北斗系统实测数据的试验分析表明:机动后轨道快速恢复时间由24 h缩短为4 h,SLR评估的预报2 h轨道视向精度优于1 m,UERE精度优于1.5 m,有效解决了轨位偏置GEO卫星的轨道快速恢复问题.

Subsatellite point for geostationary satellite（GEO） needs to be retained based on the continual orbit maneuver, especially for GEO satellite of partial subsatellite point. How to recover orbit rapidly for GEO satellite based on short-arc tracking is the key factor to improve the service performance and usability of the navigation system. Due to its geostationary feature, GEO satellite＇s orbit parameters are strongly correlated with the clock corrections parameters in precise orbit determination （POD） using L-band pseudorange data, which needs supports by the time synchronization technique. This paper presents an orbit rapid recovery method based on satellite clock offset and station clock offset. The satellite-ground time synchronization is realized by satellite-earth wireless two-way method, and the ground-ground time synchronization is realized by constellation combining orbit determination method. The precise orbit determination is realized based on pseudorange and phase data without clock offset. A new method of parameters decorrelation based on prior restriction and a short-arc orbit determination method based on the restriction by long-arc orbit determination are brought forward. The experiments based on ground data results indicate that the time of orbit recovery after maneuver is shortened from 24 h to 4 h. The 2-hour orbital prediction in radial component is better than 1 m, which is evaluated SLR data. User equivalent range error （UERE） is better than 1.5 m, and the precision is stable. The orbit recovery for GEO satellite of partial subsatellite point has come true.