中文摘要：

针对有限元软件ANSYS在分析计算天线变形表面误差时存在的问题，提出了一种基于拟合抛物面的表面形状误差改进算法,推导了精确计算变形反射面轴向、法向与径向误差的公式,分别采用改进算法与ANSYS软件对某7．3m圆抛物面天线多种工况下的表面误差进行了分析，结果证明该方法是正确的，可作为天线超差的二次判据。

英文摘要：

It is a key to analyze the electrical performances of antenna that the surface errors of distorted reflector are obtained accurately. An improved method to compute surface errors of antenna is presented against the problem caused by employing the unprecise method in ANSYS software to analyse the corresponding errors in distorted reflectors. The mathematic formulae to compute the errors in the axial, normal and radial directions of distorted surface are deduced in detail. The surface errors of a 7.3 m parabolic reflector antenna working under different conditions in engineering are anlayzed and calculated. The comparison of results by ANSYS software with that of improved method is obtained simultaneously. The simulation results verifiy the correctness and accuracy of improved method. Its application in engineering can reduce the cost of antenna deign and provide the precise error information of distorted antenna for electrical designer.