Transmission Impairment Mitigation for Single-Sideband Signals by Optical Phase Conjugation

We experimentally demonstrate an optical phase conjugation (OPC) enhanced transmission system based on the Kramers-Kronig direct detection scheme. The single-sideband signal is modulated at 80-Gb/s 16-QAM with orthogonal frequency-division multiplexing. In the 180-km transmission experiment, the OPC surpasses digital chromatic dispersion compensation in Q factor, optimum launched optical power (LOP) and optical signal-to-noise ratio (OSNR) sensitivity. The improvement in Q factor, optimum LOP and OSNR sensitivity are 0.9 dB, 1.0 dB, and 1.7 dB respectively. The superiority of OPC over pure optical dispersion compensation is also analyzed by simulation. The results indicate that the OPC is an effective means to enhance the transmission performance of single-sideband signals.