This paper presents a two-elements based, dual polarized, single layer, patch antenna array with improved isolation between transmit (Tx) and receive (Rx) ports for 2.4 GHz in-band full duplex (IBFD) or simultaneous transmit and receive wireless applications. The differential feeding deployed at the Rx port effectively suppresses the coupling which is termed as self-interference from the Tx port to achieve high Tx–Rx interport isolation. A simple 3 dB/180° ring hybrid coupler with nice amplitude and phase balance characteristics has been used for differential Rx operation. The mathematical description for a differential feeding based self-interference cancellation mechanism is also presented for the proposed dual polarized IBFD antenna array. The measurement results for the implemented prototype of the antenna array demonstrate very nice levels of Tx–Rx interport isolation. The implemented single layer, compact antenna array presents 10 dB return-loss bandwidth of more than 50 MHz for both Tx and Rx ports. The prototype achieves >80 dB peak interport isolation and 75 dB (65 dB) isolation in 20 MHz (50 MHz) bandwidth.

中文翻译：

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双极化、单基地天线阵列，具有改进的 Tx–Rx 隔离，适用于 2.4 GHz 带内全双工应用

本文提出了一种基于二元、双极化、单层的贴片天线阵列，其发射之间的隔离度有所提高（吨X) 并接收 (RX) 端口，用于 2.4 GHz 带内全双工 (IBFD) 或同时发送和接收无线应用。差动馈电部署在RX端口有效地抑制了被称为自干扰的耦合吨X端口实现高吨X–RX口岸隔离。具有良好幅度和相位平衡特性的简单 3 dB/180° 环形混合耦合器已用于差分RX手术。还针对所提出的双极化 IBFD 天线阵列提出了基于差分馈电的自干扰消除机制的数学描述。天线阵列的实施原型的测量结果显示出非常好的水平吨X–RX口岸隔离。实施的单层紧凑型天线阵列提供 10 dB 回波损耗带宽，两者均超过 50 MHz吨X和RX港口。该原型在 20 MHz (50 MHz) 带宽内实现了 >80 dB 的峰值端口间隔离和 75 dB (65 dB) 的隔离。