Open AccessPerformance analysis of coherent optical 8-star QAM systems using decision-aided maximum likelihood phase estimation
Author(s) -
Hongyu Zhang,
Pooi Yuen Kam,
Yu Chen
Publication year - 2012
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.20.009302
Subject(s) - quadrature amplitude modulation , laser linewidth , bit error rate , optics , phase shift keying , monte carlo method , quadrature (astronomy) , phase modulation , star (game theory) , qam , computer science , physics , algorithm , phase noise , mathematics , laser , statistics , astrophysics , decoding methods
An approximate bit-error rate (BER) expression of 8-star quadrature amplitude modulation (QAM) in the presence of a phase estimation error is derived. The accuracy of the approximate BER is verified via numerical integration of the conditional BER and the Monte-Carlo (MC) simulations. This approximation allows quick estimation of the BER performance and prediction of laser linewidth tolerance, and also facilitates optimization of the ring ratio.