The design, simulations and measurement results of a dual frequency feed horn operating at 35.75 GHz (Ka-band) and 94.05 GHz (W-band) are presented. The horn is designed to be used as a feed for a multifrequency atmospheric radar. The design is composed of three parts, a spline profile horn, a waveguide diplexer with Ka- and W-band ports orthogonal to each other and a Ka-band waveguide iris filter. The filter is used to achieve greater than 70 dB isolation between the Ka- and W-band ports. Directivities of 21 dB and 26 dB are achieved at Ka and W-band, respectively and a −12 dB beam width of 31 and 21 degrees has been achieved at Ka- and W-band. Measured patterns at both operating frequencies along with S-parameter measurements of the filter and the feed horn assembly are in good agreement with the simulation results.

中文翻译：

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用于多频大气雷达的紧凑型双波段馈电系统

介绍了工作在 35.75 GHz（Ka 波段）和 94.05 GHz（W 波段）的双频馈电喇叭的设计、仿真和测量结果。该喇叭被设计用作多频大气雷达的馈源。该设计由三部分组成：样条剖面喇叭、具有相互正交的 Ka 和 W 波段端口的波导双工器以及 Ka 波段波导虹膜滤波器。该滤波器用于在 Ka 和 W 波段端口之间实现大于 70 dB 的隔离。在 Ka 和 W 波段分别实现了 21 dB 和 26 dB 的方向性，在 Ka 和 W 波段分别实现了 31 度和 21 度的 -12 dB 波束宽度。两种工作频率下的测量模式以及滤波器和馈电喇叭组件的 S 参数测量值与模拟结果非常吻合。