A 60 GHz CMOS Full-Duplex Transceiver and Link with Polarization-Based Antenna and RF Cancellation

Abstract

This paper presents a fully integrated 60 GHz direct-conversion transceiver in 45 nm SOI CMOS for same-channel full-duplex (FD) wireless communication. FD operation is enabled by a novel polarization-based wideband reconfigurable self-interference cancellation (SIC) technique in the antenna domain. The antenna cancellation can be reconfigured from the IC to combat the variable SI scattering from the environment during in-field operation. A second RF cancellation path with $ > 30\;\text{dB}$ gain control and $ > 360^{\circ}$ phase control from the transmitter (TX) output to the LNA output further suppresses the residual SI to achieve the high levels of required SIC. With antenna and RF cancellation together, a total SI suppression of $ > 70\;\text{dB}$ is achieved over a cancellation bandwidth of 1 GHz and can be maintained in the presence of nearby reflectors. In conjunction with digital SIC (DSIC) implemented in MATLAB, a FD link is demonstrated over 0.7 m with a signal-to-interference-noise-and-distortion ratio (SINDR) of 7.2 dB. To the best of our knowledge, this work achieves the highest integration level among FD transceivers irrespective of the operation frequency and demonstrates the first fully integrated mm-wave FD transceiver front-end and link.