The numerical optimization results of constant thickness septum polarizer’s performances for various operating fractional bandwidths (FBW) are presented in the paper. The polarizer’s structure includes a common input square waveguide, a constant thickness septum with several steps, and two output rectangular waveguides. The polarizer design of 2-, 3-, 4-, and 5-step septums is optimized for different narrow and wide operating FBWs to obtain the simultaneously maximum values of cross-polarization discrimination and isolation between rectangular ports and return losses. The optimized dimensions of the septums for FBW = 5, 10, 15, 18, and 20% are presented. Based on the obtained results, Q- and K-band prototypes were manufactured and their performances were measured. The measurements of the prototypes are in good agreement with simulations. These optimization results can be widely used for the development of septum polarizers and prediction of their performances for various FBW in the required frequency range.

中文翻译：

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适用于各种部分带宽的最佳隔膜偏振器设计

论文中给出了不同工作分数带宽 (FBW) 下恒定厚度隔膜偏振器性能的数值优化结果。偏振器的结构包括一个公共输入方形波导、一个具有多个台阶的恒定厚度隔膜和两个输出矩形波导。2阶、3阶、4阶和5阶隔膜的偏振器设计针对不同的窄和宽工作FBW进行了优化，以同时获得矩形端口和回波损耗之间的交叉极化鉴别和隔离的最大值。展示了 FBW = 5、10、15、18 和 20% 的隔膜的优化尺寸。根据获得的结果，制造了 Q 波段和 K 波段原型并测量了它们的性能。原型的测量结果与模拟非常吻合。