考虑太阳照射的地基面天线机电耦合分析

下一代深空探测的地基面天线的面精度要求达到亚毫米级,必须考虑太阳照射导致的温度的影响。针对这一问题,以"嫦娥工程"的40 m通信面天线为研究对象,根据天线的地理位置和时间日期,计算天线受到的热流密度;考虑对流、传导和辐射三种传热方式计算天线的温度分布,并用某7.3 m卡式天线设计温度试验,结果表明温度分析是有效的;将温度作为载荷计算天线的结构变形;根据天线远区的电场公式计算电性能,并提取增益损失、副瓣电平和指向误差等主要电性能指标。仿真结果表明,温度对电性能的影响不但体现在结构变形的均方根值上,更与变形的分布形式密切相关。分析的方法和结论可用于指导下一代面天线结构设计,也可供同类型面天线设计时参考。

Electromechanical Coupling Analysis of Ground Reflector Antennas in Clear-day Environment

Operational design criteria of the next generation reflector antenna for deep space exploration is about 0.1mm,so the effect of thermal structural deformation on antenna electromagnetic performance must be researched carefully.For this engineering problem,the 40m reflector antenna of "Change Project" is considered as research object.The heat flux due to solar on antenna is calculated based on geographical position,date and time.The temperature distribution of antenna is obtained,considering three heat transfer ways: convection,conduction and radiation;and temperature experiment is designed via a 7.3 m Cassegrain antenna.Results of the experiment indicate that: the temperature model is valid;thermal-structure analysis is proceed through ANSYS.Electrical parameters of antenna is calculated by far field patterns formal,and three main electrical properties parameters including gain loss,sidelobe level and pointing error are studied mainly.The analysis result shows that,the effect of temperature on electromagnetic performance does not only depend on RMS of structure deformation,but also depend on the distribution of deformation.The analysis method and results could be used for reference on next generation reflector antenna design.