Zero mean carrier recovery

摘要

A method of data symbol recovery in a coherent receiver of an optical communications system. Two or more SYNC bursts, having a known symbol sequence and periodicity, are processed to derive an estimate of a frequency offset ”f between a transmit laser and a Local Oscillator (LO) of the receiver. A phase rotation º(n) is computed based on the estimate of the frequency offset ”f, and applied to a plurality of data symbol estimates to generate corresponding rotated symbol estimates. The rotated symbol estimates are then filtered to generate corresponding decision values of each data symbol.