Title :
Electrical Mitigation of Penalties Caused by Group Delay Ripples for Different Modulation Formats
Author :
Xia, Chunmin ; Rosenkranz, Werner
Author_Institution :
Kiel Univ., Kiel
fDate :
7/1/2007 12:00:00 AM
Abstract :
Electrical equalizers are proposed to mitigate the distortions caused by group delay ripples (GDRs) of cascaded optical filters (e.g., fiber Bragg gratings for chromatic dispersion (CD) compensation). Different electrical equalizers including feedforward equalizer (FFE), decision-feedback equalizer (DFE), nonlinear FFE-DFE, and maximum-likelihood sequence estimator are investigated and compared comprehensively for four different modulation formats: ON-OFF keying, optical duobinary, optical single sideband, and differential phase-shift keying. Especially, we find that the relationship of electrical equalization performance on the modulation format is very similar for the mitigation of GDR and CD.
Keywords :
Bragg gratings; amplitude shift keying; decision feedback equalisers; differential phase shift keying; maximum likelihood sequence estimation; optical communication equipment; optical fibre communication; optical fibre dispersion; optical fibre filters; optical modulation; ON-OFF keying; cascaded optical filters; chromatic dispersion compensation; decision-feedback equalizer; differential phase-shift keying; electrical equalizers; electrical mitigation; feedforward equalizer; fiber Bragg gratings; group delay ripples; maximum-likelihood sequence estimator; nonlinear FFE-DFE; optical duobinary modulation; optical single sideband modulation; Chromatic dispersion; Decision feedback equalizers; Delay; Fiber nonlinear optics; Maximum likelihood estimation; Nonlinear distortion; Nonlinear optics; Optical distortion; Optical filters; Optical modulation; Decision-feedback equalizer (DFE); electrical equalizers; feedforward equalizer (FFE); group delay ripples (GDRs); maximum likelihood sequence estimator; modulation formats;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2007.898814