2.4 GHz dual polarised monostatic antenna with simple two-tap RF self-interference cancellation (RF-SIC) circuitry

This Letter presents a dual polarised monostatic patch antenna with a simple two-tap RF/analogue domain-based self-interference cancellation (SIC) (RF-SIC) circuitry to achieve high interport isolation in a comparatively wider bandwidth for a 2.4 GHz in-band full duplex wireless transceiver. A brief mathematical description for the deployed two-tap RF-SIC is also presented to provide insight into self-interference (SI) suppression in a comparatively wider bandwidth. The implemented antenna with a two-tap RF-SIC circuitry achieves around 80 dB T-x-R-x isolation for a 20 MHz bandwidth in addition to more than 90 dB peak isolation for measurements performed in a lab environment where SI may result from the nearby placed objects. The deployed two-tap RF-SIC circuit can be tuned to effectively cancel out SI caused by reflections of the radio signal from the surroundings. Moreover, an 80 dB isolation bandwidth can be tuned within a 10 dB return loss bandwidth of the implemented dual polarised antenna.