基于单站CCD漂移扫描光电设备的同步轨道目标测定轨

地基光电观测在同步轨道目标监测领域具有重要作用.为评估单站光电设备对同步轨道目标的实际测定轨能力，利用上海天文台佘山站1.56m望远镜，采用CCD漂移扫描光电技术，对3颗北斗同步卫星开展试验观测，基于卫星精密星历评估目标的测定轨外符精度.结果表明:同步轨道目标的天文定位在方位和俯仰方向上的外符精度均好于0.3"；在单圈次观测情况下，尽管轨道预报精度较低，约为数千米量级，但是观测弧段内定轨精度可优于百米；在多圈次观测情况下，轨道改进效果显著，定轨精度优于50m，外推至4d的轨道预报精度为百米量级.此外，定量评估了每晚不同观测时间跨度下同步轨道目标的测定轨精度，为单站光电设备实际应用提供了参考. 

Orbit Determination for Geostationary Earth Orbit Targets Based on the CCD Drift-scan Photoelectric Telescope at One Single Stationormalsize

As a passive measurement method, the ground-based photoelectric observation is not limited by the equipment on the satellite and can be used to measure most of Geostationary Earth Orbit (GEO) targets above the station. The ground-based photoelectric observation has the advantages of low operating cost, strong intuition and high measurement precision, hence it can play an important role in monitoring the GEO targets. In order to evaluate the actual monitoring ability for GEO targets based on the photoelectric telescope at one single station, observation experiments of 3 Beidou GEO satellites are carried out by 1.56-meter telescope with CCD drift-scan photoelectric technology of Shanghai Astronomical Observatory. The external precisions are estimated by the precise ephemeris of the satellites. The results show that the accuracy of the celestial positioning of the GEO satellites is better than 0.3" in both azimuth and elevation. In the case of single observation pass, although the accuracy of orbit prediction is low, the orbit determination accuracy during observation arc is better than 100m. The effect of orbit improvement based on multi-pass of observations is obvious. In the absence of orbit control, the orbit determination accuracy is better than 50m, and the prediction precision of extrapolating to 4-day is about the order of hundreds of meters. In addition, the accuracy of the orbit prediction of the GEO target in the case of different observation time span is quantitatively evaluated, which can provide the reference for the practical application of the CCD drift-scan photoelectric telescope at one single station.