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Blind adaptive equalization of polarization-switched QPSK modulation. | LitMetric

Blind adaptive equalization of polarization-switched QPSK modulation.

Opt Express

Department of Electronic and Electrical Engineering, University College London (UCL), London, UK.

Published: April 2011

AI Article Synopsis

Article Abstract

Coherent detection in combination with digital signal processing has recently enabled significant progress in the capacity of optical communications systems. This improvement has enabled detection of optimum constellations for optical signals in four dimensions. In this paper, we propose and investigate an algorithm for the blind adaptive equalization of one such modulation format: polarization-switched quaternary phase shift keying (PS-QPSK). The proposed algorithm, which includes both blind initialization and adaptation of the equalizer, is found to be insensitive to the input polarization state and demonstrates highly robust convergence in the presence of PDL, DGD and polarization rotation.

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Source
http://dx.doi.org/10.1364/OE.19.008533DOI Listing

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