一种Ka/EHF频段分波器(OMJ)的设计

Design of A Ka/EHF Band Orthomode Junction (OMJ)

针对传统分波器影响高频方向图的问题,提出了一种新型的Ka/EHF频段分波器设计方法。与传统分波器相比,该分波器具有低损耗、低驻波、高频段隔离的优点,其通过使用皱褶波纹滤波器和sin^2曲线过渡,实现了Ka、EHF频段信号的低损耗分离,分布式参数综合设计的波纹滤波器对高频信号产生了极佳短路面,sin^2函数曲线过渡较好地抑制了高次模。设计、加工和测试了样机,接收频段的回波损耗小于-22 dB,发射频段的回波损耗小于-25.2 dB,仿真结果与测试结果基本吻合,验证了方法的正确性和有效性。

To solve the problem that the radiation pattern of feeding horn at high-frequency is often distorted by the high-order modes,a novel design method of orthomode junction(OMJ)for Ka/EHF dual bands is presented.Compared with conventional OMJ,this OMJ has advantages of low cross polarization,low return loss and high isolation.The OMJ acts to split the signal into Ka band and EHF band by using corrugated filter and sin^2 transitional transform.The corrugated filter with distributed parameter provides a short face on OMJ.And the transitional transform with sin^2 function curve suppresses high order modes effectively.The designed OMJ is fabricated and measured.Measured results agree very well with simulated ones and the return loss is less than-22 dB in receiving band,the return loss is less than-25.2 dB in transmitting band.