SPM and phase-noise cancellation using time-division-multiplexed and intensity-modulated pilot symbols

抄録

We propose a novel SPM and phase-noise cancellation scheme using pilot symbols. The pilot symbols are intensity-modulated and time-division-multiplexed with a modulated optical signal. Each pilot symbol has the same optical intensity as the multiplexed modulated symbol and therefore has the same nonlinear phase shift caused by self-phase modulation (SPM). Additionally, each pilot symbol has the same phase noise as the modulated symbol because it is generated by the same laser diode (LD). At the receiver side, self-homodyne detection is performed using the pilot symbols as absolute optical phase references. The performance of the scheme was investigated by numerical simulations of 50-km optical fiber transmission of 16-ary quadrature amplitude modulation (16QAM) signals.