An adaptive algorithm of fine synchronization for CO-OFDM system

An adaptive algorithm of fine synchronization for coherent optical orthogonal frequency division multiplexing (CO-OFDM) transmission system is proposed. The whole synchronization is separated into two steps. In the first step, we use an auto-correlation-style algorithm to achieve the coarse symbol synchronization. In the second step, the proposed algorithm is used to achieve the fine synchronization. The merit of the proposed algorithm is that it can realize fine synchronization under different environments without adjusting the detect-threshold of timing metric in a dynamically reconfiguration network. The numerical experiment result demonstrates that the proposed algorithm achieves fine synchronization under different signal noise ratio (SNR) conditions after 6 fiber-spans transmission.