Pulse-carver-free RZ-64 QAM transmitter using RZ drive signal with electronic CD pre-compensation

Abstract

We propose a novel technique that can generate an optical return to zero quadrature amplitude modulation (RZ-QAM) signal without using a pulse carver. This technique permits electronic pre-compensation of the chromatic dispersion (CD) because the envelope of the optical waveform is not restricted by pulse carver performance. We successfully generate polarization multiplexed RZ-64 QAM signals (72Gbit/s) with and without electronic CD pre-compensation. By utilizing 50% CD pre-compensation, the Q-factor is improved by 0.4dB after 240km (+4900ps/nm) transmission.