Dispersion compensation of wavelength-division multiplexed signals using waveband shift-free optical phase conjugators

Abstract

Dispersion compensation performance of a waveband-shift-free optical phase conjugator (WBSF-OPC) on multi-span transmission of 20-Gbit/s quadrature phase-shift keying × 3-ch. WDM signals is numerically investigated. Provided that linear distortion owing to chromatic dispersion is considered, the middle channel of the WDM signals is perfectly compensated by WBSF-OPCs. Further, it is shown that the 3-channel WDM signals with a 2.2-THz optical frequency interval can be transmitted via a 640-km transmission fiber owing to the WBSF-OPCs, although their signal qualities degrade owing to residual dispersion.