Co-polarized monostatic antenna with high Tx-Rx isolation for 2.4 GHz single channel full duplex applications

This article presents a linear co-polarized (same polarization for transmit and receive modes), proximity coupled monostatic patch antenna with high port to port RF isolation for 2.4 GHz single channel full duplex (SCFD) wireless applications. The presented proximity coupled monostatic patch antenna deploys differential feeding for receive (R-x) mode to significantly suppress RF leakage from transmit (T-x) port and external single-tap self-interference cancellation (SIC) circuit provides additional interport isolation. The measurements for implemented prototype of antenna in lab environment provide around 50 dB T-x-R-x isolation for 50 MHz bandwidth in addition to better than 75 dB peak isolation. Moreover, the deployed single-tap RF SIC circuit can be used to suppress SI resulted from environmental reflections and 50 MHz SIC bandwidth with 50 dB isolation can be tuned within antenna's 10 dB return loss impedance bandwidth of 150 MHz.