A Digitally-Assisted Self-Interference Cancellation for Full-Duplex Phased Array Radar

Full duplex (FD) technology has its unique advantages of potentially doubling the spectrum efficiency and has been widely studied. The biggest challenge in FD technology is how to conduct an effective radio frequency (RF) self-interference cancellation (SIC) scheme. The traditional approach is to reconstruct all the interference signals and subtract them from the received signal. However, when applied in multi-antenna systems, the RF SIC complexity significantly increases with the antenna number. In this paper, a phased array-based FD transceiver is proposed which integrates both radar detection and wireless communication functions into a single device. In this transceiver, a simplified RF SIC architecture is proposed by exploring the structural symmetry of the phased array antenna deployed. Simulation results show that the proposed method can achieve the same SI cancellation as the traditional method with significant complexity reduction in RF SIC circuits design. Furthermore, as fewer RF circuits are used, less noise interference will be introduced. This method demonstrates a quite promising solution for FD design in multi-antenna applications.