变形双反射面天线的机电耦合分析方法

Electromechanical coupling analysis method of deformeddual-reflector antennas

双反射面天线广泛应用于雷达、卫星通信和射电天文等领域,针对变形双反射面天线的电性能求解问题,本文提出了基于物理光学法的机电耦合分析方法.深入分析了双反射面天线主副反射面变形对天线电性能的影响,通过将主副反射面轴向变形转换为天线远场积分公式中的相位误差影响项,建立了反射面表面结构位移场与天线远场之间的机电耦合关系.进一步将相位误差影响项作一阶泰勒级数展开,使得结构误差从天线远场积分运算中独立出来,通过构建包含主副反射面变形信息的误差矩阵可实现变形反射面天线远场的快速计算.对一个2.2 m天线进行案例分析,结果验证了所提方法的正确性.

Dual-reflector antennas are common in radar, satellite communications, radio astronomy, and other applications. Toanalyze the electrical performance of a deformed dual-reflector antenna, an electromechanical coupling analysis methodbased on Physical Optics is proposed. The influence of the main and subreflector deformation of the dual-reflectorantennas on the electrical properties is thoroughly investigated, and the electromechanical coupling relationship betweenthe displacement field of the surface structure of the reflector and the far field of the antenna is established by convertingthe axial deformation of the main and subreflector into the phase error influencing term in the antenna far-field integralformula. Furthermore, the phase error influence term grows as a first-order Taylor series so that the structural error isindependent of the antenna far-field integration operation and the fast calculation of the far field of the deformed dualreflectorantenna is realized by constructing an error matrix containing the main and subreflector deformationinformation. A case study of a 2.2 m antenna validates the correctness of the proposed method.