俄月球-全球等探测任务中的无线电科学试验

Radio Science Experiments in Russian“Luna-Recourse” “Luna-Glob”Projects

俄罗斯航天局正在规划和推进新的月球探测计划,包括月球资源和月球全球探测任务,它们搭载了3个无线电科学载荷：2个无线电信标机分别安装在2个着陆器上,1个Ka波段接收机安装在月球全球轨道器上.信标机发射频率为8.4GHz和32GHz.8.4GHz的微波信号将被发回地球,利用地面VLBI监测网对信号进行测量,其结果可用于精密的天体力学观测及导航,还能用于月球天平动研究;32GHz信号将用于定轨和月球重力场研究.Ka波段信号天线轴指向着陆区天顶方向,信号由轨道器接收.本文基于对Ka波段信号多普勒频移的精确测量,通过研究着陆区附近重力场的微小变化（约3~5mGal精度）,探讨月球重力场的不均匀性,其测量数据的空间分辨率约为20km.

These years,the Russia Space Agency is planning a couple of new lunar orbiting and landing explorations,the luna-resource and luna-glob projects.Three kinds of radio scientific payloads will be installed on them:two radio beacons,installed on Luna-Resource and Luna-Glob Landers separately,and a Ka-band receiver installed on Luna-Glob orbiter.The beacons will irradiate signals at two radio frequency bands of 8.4 GHz and32 GHz.The 8.4GHz signals will be transmitted to the Earth,where the VLBI ground based network will be used for celestial mechanics experiments and as a navigation tool.It will be possible to measure the beacon's positions with accuracy about 1cm and to register Moon's libration.The 32 GHz band will be used as a kind of orbiter navigation tool and for lunar gravity field investigation.The Ka band signal will be directed to local zenith and will be received by orbiter's receiver.Investigation of non-uniformity of lunar gravity field(experiment INGL)will be performed in vicinity of landing regions with accuracy 3~5mGal.The spatial resolution will be about 20 km.The experiment is based on precise Doppler shift measurement.