Low-Complexity Nonlinear Self-Interference Cancellation for Full-Duplex Radios

Abstract

Full-duplex radio, expected to double the spectral efficiency, is one of the promising technologies for fifth generation (5G) communication. To overcome self-interference, which is a main obstacle to full-duplex radio, various self-interference cancellation (SIC) techniques have been developed. For digital SIC, the nonlinearity of a transmitter occurred by a power amplifier is a main bottleneck. The nonlinear SIC methods proposed in prior work are not feasible due to high computational complexity, or the cost of extra hardwares. In this paper, we propose the pre-calibration method that linearizes the transmitter, and applies only linear SIC. Numerical results confirm that the proposed SIC method shows 43 dB cancellation performance while the existing method shows only 18 dB in fast fading channels.