In this letter, an efficient and electrically compact cavity-backed self-triplexing antenna using a substrate integrated waveguide (SIW) technique is proposed. The antenna model is nested with an inverted “T”-shaped cavity and convert the rectangular SIW cavity into the two quarter mode (QM) and ahalf mode cavity (HM) approximately; excited through a coax probe and two micro-strip feed line separately. The proposed model operates at three distinct frequencies at 9.37 GHz, 9.86 GHz, and 10.36 GHz used for X-band wireless and radar communication systems. The self-triplexing feature is obtained with the mode perturbation concept and adequate intrinsic isolation of >31 dB is observed among three input ports. The proposed antenna possesses a minimum frequency ratio, uni-directional radiation patterns with high gain, and better efficiency.

中文翻译：

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基于三馈SIW的自三工天线，用于X波段应用

在这封信中，提出了一种使用衬底集成波导（SIW）技术的高效且电紧凑的背腔自双工天线。天线模型嵌套有一个倒置的“ T”形空腔，并将矩形的SIW空腔近似转换为四分之一模（QM）和半模腔（HM）。通过同轴探头和两条微带馈线分别激发。提议的模型在X波段无线和雷达通信系统所用的9.37 GHz，9.86 GHz和10.36 GHz的三个不同频率下运行。通过模式扰动概念获得了自三工特性，并且在三个输入端口之间观察到了大于31 dB的足够的固有隔离度。所提出的天线具有最小的频率比，具有高增益的单向辐射方向图和更高的效率。