深空测控网干涉测量系统在“鹊桥”任务中的应用分析

在"嫦娥4号"任务的第一阶段—"鹊桥"阶段,北京航天飞行控制中心利用佳木斯及喀什深空站对"鹊桥"进行了干涉测量观测,获取了实时与事后的高精度测角观测量,有效支持了任务的实施。两深空站需同时完成测控任务,无法交替射电源观测来进行系统差标校,基于此系统采用了长时间隔、在航天器观测前及双站结束后观测射电源的标校方法,在地月转移段、月球至L2转移段、Halo轨道形成段开展了多次干涉测量观测,所获得的时延、时延率结果直接应用于事后联合轨道确定,结果表明:深空网的时延观测精度约为3 ns。

Application of Deep Space VLBI System in Queqiao Mission

In Queqiao mission, the first stage of Chang''e-4 mission,Queqiao mission,Jiamusi and Kashi deep space stations were used to conduct VLBI(Very Long Baseline Inteferometry) observation to the relay satellite. Real-time and post-time high-precision angular measurement results were obtained,which effectively supported the mission implementation. In the mission,the two deep space stations need to complete the TT&C tasks at the same time,so they cannot alternate the radio source and spacecraft observation to calibrate the system error. Based on this system,a long time interval calibration method was adopted to observe the radio source before and after the spacecraft observation. Multiple interferometric measurements were carried out in the lunar transfer section,the Lunar to L2 transfer section and the Halo orbital formation section. The results show that the observation accuracy of the deep space network is about 3ns.