深空探测中，当行星探测器被太阳遮掩时，太阳风等离子体扰动会带来信号的闪烁和传播的延时，精确的测定轨需要对等离子体进行校正。传统的方法采用太阳风电子密度经验模型，或使用探测器的多频点测速、测距数据进行太阳风电子密度的测量。本项目将利用甚长基线干涉阵(VLBI)研究太阳风电子密度分布的建模方法，用于探测器太阳风等离子体时延和时延率的校正，并利用上海天文台自主研发的卫星定轨软件进行验证。项目也将利用VLBI观测的探测器和射电源开展太阳风对信号的行星际闪烁研究。本项目的研究成果可用于我国未来火星探测的太阳掩星观测，也是VLBI技术应用于太阳风研究的技术储备。

In deep space exploration, spacecraft such as Mars Express(MEX) has experienced superior solar conjunctions. The conjunctions cause severe degradation of radio signals when the line of sight between the Earth and the spacecraft passes near to the solar corona region. The solar plasma will cause interplanetary scintillation, time delay and delay rate, the plasma correction must be taken in high-precision orbit determination. The traditional method use solar wind electron density empirical model, or use multi frequency range or Doppler to measure electron density. This project will use very long baseline interferometry(VLBI) to measure electron density, use it on plasma correction, verified it with Mars Satellite Orbit Determination Software which is developed by Shanghai Astronomical Observatory. The project will also research interplanetary scintillation of spacecraft and quasar signals caused by solar wind. The result of the project could be used in solar conjunction data process during China's future Mars exploration, and it's also the technical reserves of VLBI application in solar wind research.