极小极大值法在赋形反射面天线设计中应用研究  

Application of Minimax method in the design of shaped reflector antenna

作　　者：张新刚[1] 吴刚[1] 钟鹰[1] 

机构地区：[1]中国空间技术研究院西安分院,陕西西安710100

出　　处：《电波科学学报》2011年第2期280-285,共6页Chinese Journal of Radio Science

摘　　要：为了使星载天线的远场方向图与服务区的形状相匹配,并在服务区内获得高的增益和交叉极化隔离度,通过雅可比-贝塞尔(Jacobi-Bessel)函数来表示反射面的形状,应用极小极大值(Minimax)算法对单偏置抛物反射面天线进行优化设计。在优化过程中,把表征反射面形状的展开系数作为优化参数,利用物理光学(PO)与物理绕射理论(PTD)相结合的方法来计算远场,同时考虑了天线的增益和交叉极化隔离度,并对反射面的形变量加以限制来保证最终优化得到的星载反射面天线能够应用现有技术和材料加工出来。最后以产生一个覆盖巴西全部领土的赋形波束为例进行了优化设计,数值仿真结果表明:在服务区内主极化增益都高于28.5 dBi,交叉极化隔离度都在21 dB以上。To generate a far field pattern of satellite mounted antenna matching the coverage area, and obtain the high gain and the cross polarization isolation, the application of Minimax method in the design of a single offset shaped reflector antenna represented by the Jacobi-Bessel function is addressed. The expansion coefficients of the surface are set as the parameters to be optimized and a combined method of physical optics（PO） and physical theory of diffraction（PTD） is used to calculate the far field pattern. The gain and the cross polarization isolation are regarded as the optimization aims. In order to avoid the creation of un-realizable reflector shapes, a limit is added to the deviation in the z-direction from the original paraboloid. Finally, the contoured beam covering the Brazilian territory is optimized. The results show that the copolar gain is above 28.5dBi and the cross polarization isolation is better than 21dB in all coverage areas.

关 键 词：MINIMAX 赋形波束 反射面天线 优化 

分 类 号：TN821[电子电信—信息与通信工程]