Transparent performance monitoring of RZ-DQPSK systems employing delay-tap sampling

Abstract

Feature Issue on Transmission in Optically Transparent Core NetworksThe emerging transparent optical networks, employing spectrally efficient modulation formats, require new methods for supervision of signal quality in order to maintain control over the transmission in all-optical domains. Optical performance monitoring of optical signal-to-noise ratio, chromatic dispersion, and polarization-mode dispersion in return-to-zero differential quadrature phase-shift keying signals is demonstrated using asynchronous delay-tap sampling and pattern recognition algorithms. Precise estimation of parameters over a broad range of impairment levels and good degradation isolation is shown by means of numerical simulation.