The Stability of USO to Mars Orbiter Influence

The China’s first Mars orbiter "YingHuo-1" (YH-1) will be launched in the near future. To solve the tracking problem of Mars satellite, the kernel payload of Ultra Stable Oscillator (USO) of “YingHuo-1” is used for frequency standard, and the transmitter generates a standard downlink radio signal. The ground astronomical Very Long Baseline Interferometry (VLBI) system will be used to receive the radio signal. In this article, to investigate the mechanism of the tracking accuracy of the orbit detemination of YH-1, the experimental data of YingHuo-1’s USO was processed, using Solar-system Model and Orbit Determination (SMOD) software system developed at Xinjing Astronomical Observatory. The real-time precise orbit determination can be supported by the simulation experimental result, when the frequency stability of USO is about 10-12.