Method and system for reducing transmission penalties associated with ghost pulses

摘要

A method and apparatus for reducing transmission penalties associated with ghost pulses in an optical signal in a transmission system includes providing phase modulation to the optical signal in the transmission system with a period of phase modulation greater than a bit period of the transmission system, wherein the phase modulation is applied to the optical signal such that the phases of at least some logical “ones” within a sequence of logical “ones” of the optical signal are modified such that the phases of the individual ghost-pulse fields from each triplet of “ones” are different, either pseudo-randomized or substantially shifted by &pgr;, thereby resulting in a reduction of the total ghost pulse. Advantageously, there is no need to synchronize the timing of the phase modulation with the timing of the power profile of the optical signal.