Simple sampling clock synchronisation scheme for reduced-guard-interval coherent optical OFDM systems

摘要

A simple data-aided scheme for sampling clock synchronisation inreduced-guard-interval coherent optical orthogonal frequency divisionmultiplexing (RGI-CO-OFDM) systems is proposed. In the proposed scheme, thesampling clock offset (SCO) is estimated by using the training symbols reservedfor channel estimation, thus avoiding extra training overhead. The SCO is thencompensated by resampling, using a time-domain interpolation filter. Thefeasibility of the proposed scheme is demonstrated by means of numericalsimulations in a 32-Gbaud 16-QAM dual-polarisation RGI-CO-OFDM system.