Real-time adaptive optical self-interference cancellation system for in-band full-duplex transmission

Abstract

A real-time adaptive optical self-interference cancellation (RTA-OSIC) system is proposed and demonstrated for in-band full-duplex transmission. The RTA-OSIC system is controlled automatically by adaptive algorithm running on a real-time microcontroller STM32. Modified Hooke–Jeeves (MHJ) algorithm is proposed to search the optimal optical parameters more rapidly. Experimental results show that the MHJ algorithm requires 15–25 samples to find the optimal point. The RTA-OSIC system achieves more than 22 dB cancellation depth within 0-700 MHz frequency band. Compared with the existing adaptive OSIC system which uses the Nelder–Mead Simplex algorithm, there are 60% less samples for our RTA-OSIC system with MHJ algorithm.