In this letter, a single-layer compact copolarized shorted TM _1/2,0 mode microstrip patch antenna is presented for in-band full-duplex application. Two shorted TM _1/2,0 mode patch antennas, used for transmission and reception purposes, make the structure compact. The wideband behavior of the patch antenna is obtained by fusing the two resonances, one because of the shorted TM _1/2,0 mode radiating patch and the other because of the λ/4 line resonator. To enhance the isolation between the transmitter and receiver antenna, a novel defected ground structure is used. Slots are introduced into the ground plane to create a weak field region for the basic antenna element. The other antenna element (receiver) is located in the weak field region to enhance isolation. Further enhancement in isolation is achieved by introducing a T-shaped metallic strip into the slots. The structure is proposed with the credits of compactness, enhanced bandwidth, colinear polarization, very less fabrication complexity, low profile, and high isolation. The proposed structure is fabricated and measured. The structure experimentally exhibits a bandwidth (≤ −10 dB) of 2.42–2.52 GHz with the isolation of 25 dB, peak isolation of 36 dB, and an average realized gain of 4 dBi in the entire band.

中文翻译：

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用于全双工系统的紧凑、薄型短接 TM$_{1/2,0}$ 模式平面共极化微带天线

在这封信中，介绍了一种用于带内全双工应用的单层紧凑型共极化短路 TM _{1/2,0模式微带贴片天线。}两个短接的 TM _1/2,0模式贴片天线，用于发送和接收目的，使结构紧凑。贴片天线的宽带行为是通过融合两个谐振获得的，一个是因为短路的 TM _1/2,0模式辐射贴片和另一个因为 λ/4 线谐振器。为了增强发射器和接收器天线之间的隔离，使用了一种新颖的缺陷接地结构。槽被引入接地平面，为基本天线元件创建一个弱场区域。另一个天线元件（接收器）位于弱场区域以增强隔离。通过将 T 形金属条引入槽中可以进一步提高隔离度。该结构具有紧凑、带宽增强、共线极化、制造复杂性极低、低剖面和高隔离等优点。建议的结构是制造和测量的。该结构实验显示带宽（≤ -10 dB）为 2.42–2.52 GHz，隔离度为 25 dB，峰值隔离度为 36 dB，