Full‐Duplex RF Designs

Abstract Full‐duplex wireless involves simultaneous transmission and reception at the same frequency, promising significant enhancement in wireless network performance, such as spectral efficiency, link capacity, and network latency. For full‐duplex radios, >100 dB self‐interference suppression is needed and must be performed across the antenna, radio frequency (RF), analog, and digital domains. Self‐interference cancellation (SIC) in the RF domain, where a replica signal is tapped from the transmitter output and injected prior to receiver down‐conversion, has been used in many full‐duplex wireless systems. In this article, we describe different SIC architectures and unveil the challenges associated with full‐duplex RF SIC design. Discussion and review of some full‐duplex RF SIC designs are presented followed by a brief outlook for future works.