Carrier phase recovery without pilot sub-carriers in coherent optical OFDM transmission systems

Abstract

A carrier phase recovery method for optical transmission format of 16-QAM constellations is presented. The method can also be used in coherent optical single carrier or OFDM (CO-OFDM) system to implement blind phase recovery with low computational cost. We apply this method in 112Gb/s 1040 km CO-OFDM transmission, and compare its performance to those using the fourth-power estimator. Experimental results obtained indicate that the proposed method significantly outperform the fourth-power estimator.