GEO导航卫星多种观测资料联合精密定轨

The precise orbit determination of GEO navigation satellite with multi-types observation

针对跟踪站少、观测几何条件差以及轨道机动后GEO导航卫星精密定轨问题,提出了用激光观测数据解算无线电测距离观测数据设备时延、用CODE模型参数和多频载波相位数据进行电离层延迟精确修正的精密定轨和轨道快速恢复的处理体制.通过在轨实测数据实验证明,利用激光标定的距离观测数据组合设备时延精度优于1ns;基于3站观测数据GEO卫星精密定轨结果,RMS为0.25m;24h数据定轨结果重叠12小轨道径向互差0.55m,位置互差约1.62m;预报12h轨道重叠弧段互差为径向3.63m,位置互差8.51m;定轨结果与激光比对残差约0.10m,预报2h轨道比对残差约0.18m,预报24h轨道比对残差约2.04m.GEO卫星轨道机动后2～3h,动力学定轨结果能够恢复到与激光比对残差小于1m、与精密定轨结果比对位置互差约30m的水平.试验及分析结果表明,所提出的GEO精度定轨技术方案可靠、稳定.

Tracked only by fewer stations which are weakly distributed in geometry, some thing such as the precise orbit determination and rapid orbit recovery after maneuver of GEO navigation satellite are discussed. The methods to solute the device delay of CC transfer observation by some SLR observation, or the so called ＂CODE model and multi-frequency carrier phase data＂ arithmetic to eliminate the CC observation ionosphere delay are advanced, as well the flows of GEO POD based on multi-types observation. Some practical experimentation can testify the validity of above-mentioned methods, and their results show that the solution precision of combined device delay is in 1 ns level. The RMS of the GEO POD only based three CC observation station is about 0.248 m, the 12 h overlap orbit difference of two determination results based on 24 h span observation are 0.55 m in radial direction and 1.62 m in three dimensions. The difference between determination results based on 24 h span observation and their predicted orbits by 12 h are 3.63 m in radial direction and 8.51 m in three dimensions. Compared with SLR observation, the RMS is about 0.10 m for POD results, 0.1 m for predicted orbit by 2 h, 2.04 m for predicted orbit by 24 h. The rapid recovery orbit precision can reach 30 m position level based 2–3 h CC transfer observation after maneuver, the RMS is less than 1 m compared with SLR data. At last, the POD covariance matrix analyze show that the POD method mention above can lead to steady results which is not very sensitive to the device day bias.