Optical RF self-interference cancellation for full-duplex communication using phase modulation and sideband filtering

A novel optical approach to implement the RF self-interference cancelation for full-duplex communication using phase modulation and sideband filtering is proposed and demonstrated experimentally. By using the inherent out of phase property between the left and right sidebands of phase-modulated signal, and tuning the delay time and amplitude in optical domain to align the reference signal with the interference signal, the RF self-interference cancellation is achieved. The experimental results show that, for both 5GHz and 8GHz, the system can achieve 61- and 35-dB cancellation depth for single frequency and 1MHz bandwidth, respectively.