This paper presents a compact, dual polarized bistatic (two closely spaced transmit and receive radiators) patch antenna with excellent interport isolation performance. The presented antenna system employs differential receive mode operation for the cancellation of self-interference (SI) to achieve very high interport isolation for 2.4 GHz in-band full duplex (IBFD) applications. The presented antenna is based on two closely spaced radiators and a simple 3 dB/180° coupler for differentially excited receive mode operation. The 3 dB/180° coupler performs as a passive self-interference cancellation (SIC) circuit for the presented antenna. The small form-factor structure is realized through via interconnections between the receiving patch and SIC circuit. The prototype of the presented antenna characterizes better than 105 dB peak interport isolation. Moreover, the recorded interport isolation is more than 90 dB and 95 dB within 60 MHz and 40 MHz bandwidths, respectively. The measured gain and cross-polarization levels reflect superior radiation performance for the validation model of the proposed antenna. The presented antenna offers DC interport isolation too, which is required for active antenna applications. The novelty of this work is a compact (small form-factor) antenna structure with very high peak interport isolation along with wider SIC bandwidth as compared to previously reported antennas for full duplex applications.

中文翻译：

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紧凑的双基地天线系统，具有非常高的端口隔离，可用于2.4 GHz带内全双工应用

本文提出了一种紧凑的，双极化双基地（两个紧密间隔的发射和接收辐射器）贴片天线，具有出色的端口间隔离性能。提出的天线系统采用差分接收模式操作来消除自干扰（SI），从而为2.4 GHz带内全双工（IBFD）应用实现非常高的端口隔离。所展示的天线基于两个紧密间隔的辐射器和一个简单的3 dB / 180°耦合器，用于差分激励接收模式操作。3 dB / 180°耦合器可作为所提供天线的无源自干扰消除（SIC）电路。通过接收贴片和SIC电路之间的互连实现小尺寸结构。所展示天线的原型具有优于105 dB的峰值端口间隔离特性。此外，在60 MHz和40 MHz带宽内，记录的端口隔离度分别超过90 dB和95 dB。所测得的增益和交叉极化水平反映了拟议天线验证模型的卓越辐射性能。所展示的天线也提供直流端口隔离，这是有源天线应用所必需的。与先前报道的用于全双工应用的天线相比，这项工作的新颖之处在于其紧凑的（小尺寸）天线结构具有非常高的峰值端口隔离以及更宽的SIC带宽。所展示的天线也提供直流端口隔离，这是有源天线应用所必需的。与先前报道的用于全双工应用的天线相比，这项工作的新颖之处在于其紧凑的（小型）天线结构具有非常高的峰值端口隔离以及更宽的SIC带宽。所展示的天线也提供直流端口隔离，这是有源天线应用所必需的。与先前报道的用于全双工应用的天线相比，这项工作的新颖之处在于其紧凑的（小型）天线结构具有非常高的峰值端口隔离以及更宽的SIC带宽。