This communication reports the design of highly compact cavity-backed self-diplexing Y-shaped slot antenna for high-isolation employing quarter-mode substrate integrated waveguide (QMSIW). The proposed antenna is built by using QMSIW, Y-shaped slot and two 50 Ω feed lines. Two unequal radiating apertures are developed by inserting an Y-shaped slot on the top side of the rectangular SIW for radiation at 3.9 and 4.9 GHz for long term evolution (LTE) and public safety band (PSB) applications, respectively. By keeping another band unaltered, the proposed antenna allows any frequency band to be tuned independently. The size of antenna is highly compact due to the use of QMSIW cavity. The isolation between two ports of the antenna is greater than 34 dB. The antenna achieves 5.43 and 5.85 dBi peak gains at 3.9 and 4.9 GHz, respectively. On both the frequency bands, the antenna efficiency is greater than 85%. The antenna has a front-to-back-ratio of more than 20.6 dB and a separation from co-to-cross polarization level of more than 21 dB. Through manufacture and measurement, the designed antenna is validated.

中文翻译：

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采用四分之一模基片集成波导的高度紧凑型自双工Y形缝隙天线设计

该通讯报告了采用四分之一模式衬底集成波导 (QMSIW) 的高度紧凑型背腔自双工 Y 形缝隙天线的设计，用于高隔离度。建议的天线是通过使用 QMSIW、Y 形槽和两条 50 Ω 馈线构建的。通过在矩形 SIW 的顶部插入一个 Y 形槽来开发两个不相等的辐射孔径，分别用于 3.9 GHz 和 4.9 GHz 辐射，用于长期演进 (LTE) 和公共安全频带 (PSB) 应用。通过保持另一个频段不变，建议的天线允许独立调谐任何频段。由于使用了 QMSIW 腔，天线的尺寸非常紧凑。天线两个端口之间的隔离度大于34 dB。该天线分别在 3.9 和 4.9 GHz 下实现了 5.43 和 5.85 dBi 的峰值增益。在两个频段上，天线效率都大于 85%。该天线的前后比超过 20.6 dB，与共交叉极化电平的分离度超过 21 dB。通过制造和测量，对设计的天线进行了验证。