Tracking technology of Mars spacecraft for large radio telescope

In 2020, China will launch a Mars spacecraft composed of anorbiter and lander/rover. In this paper, the tracking techniques of the Marsspacecraft for a large radio telescope are analyzed and verifiedusing the Shanghai 65 m radio telescope (Tianma telescope). The measurementresults indicate that the pointing error caused by thermal deformation ofthe antenna body, atmospheric refraction, and the light-time effect should beconsidered when a large radio telescope is used to track the Marsspacecraft. When the light-time effect is not taken into account, thereceiving power is reduced by approximately 0.8 dB. When the elevation offset is 36and 72 arcsec, the reception capacity of the Tianma telescope is reduced byapproximately 0.8 and 3.5 dB, respectively. The results of this study thus have importantimplications for the Mars exploration.