Title :
Frequency-Domain Blind Equalization for Long-Haul Coherent Pol-Mux 16-QAM System With CD Prediction and Dual-Mode Adaptive Algorithm
Author :
Zhu, Chen ; Tran, An V. ; Chen, Simin ; Du, Liang B. ; Anderson, Trevor ; Lowery, Arthur J. ; Das, Efstratios Skafi
Author_Institution :
Dept. of Electr. & Electron. Eng., Univ. of Melbourne, Parkville, VIC, Australia
Abstract :
The combination of polarization-multiplexing (pol-mux) high-order quadrature-amplitude-modulation (QAM) format and non-data-aided (NDA) channel equalization largely enhances the spectral efficiency of the coherent optical systems. In this paper, we present a two-stage frequency-domain equalization method for long-haul coherent pol-mux NDA system with 16-QAM modulation format. Chromatic dispersion (CD) is blindly estimated and compensated in the first stage of the equalizer, while multimodulus-algorithm-assisted decision-directed multimodulus algorithm (MMA-DDMA) is designed for the second stage to further enhance the equalization performance. The proposed algorithms are experimentally demonstrated in a 80-Gb/s coherent 16-QAM system over 800-km fiber transmission and 30-ps mean differential group delay to achieve wide-range precise CD estimation and better equalization performance compared with conventional adaptive algorithms.
Keywords :
adaptive equalisers; blind equalisers; multiplexing; optical fibre dispersion; optical fibre networks; optical fibre polarisation; quadrature amplitude modulation; 16-QAM system; chromatic dispersion prediction; distance 800 km; dual mode adaptive algorithm; frequency domain blind equalization; frequency domain equalization method; long haul coherent polarization-multiplexing; multimodulus algorithm assisted decision directed multimodulus algorithm; nondata-aided channel equalization; quadrature amplitude modulation format; Blind equalizers; Optical fibers; Optical filters; Optical polarization; Optical receivers; Frequency-domain equalization (FDE); blind equalizers; coherent receiver;
Journal_Title :
Photonics Journal, IEEE
DOI :
10.1109/JPHOT.2012.2214378
