Impact of DFB-LD FM response distortion, in amplitude and phase, on FSK coherent systems

Author

Gambini, P. ; Puleo, M. ; Caponio, N. ; Vezzoni, E.

Author_Institution

CSELT, Torino, Italy

fYear

1991

fDate

23-26 Jun 1991

Firstpage

334

Abstract

The influence of amplitude and phase distortions of the FM response of DFB (distributed feedback) lasers on coherent FSK (frequency shift keying) transmission systems has been investigated. It was found that pattern effects are mainly due to phase distortions, while the IF (intermediate frequency) spectrum broadening is due to both amplitude and phase distortions. Possible remedies are described, including device selection, line coding, and phase and/or amplitude equalization of the FM response. A comparison between observed spectra and computer analysis has been performed, showing a good agreement. Transmission experiments at 140 Mb/s have been carried out, showing the predicted effects on the eye diagram

Keywords

distributed feedback lasers; frequency shift keying; optical communication equipment; 140 Mbit/s; DFB-LD FM response distortion; FM response; FSK coherent systems; IF spectrum broadening; amplitude distortion; amplitude equalization; device selection; distributed feedback lasers; eye diagram; frequency shift keying; intermediate frequency; line coding; pattern effects; phase distortions; phase equalization; Cutoff frequency; Demodulation; Diode lasers; Filters; Frequency modulation; Frequency shift keying; Laser beam cutting; Laser transitions; Phase distortion; Thermal factors;

fLanguage

English

Publisher

ieee

Conference_Titel

Communications, 1991. ICC '91, Conference Record. IEEE International Conference on

Conference_Location

Denver, CO

Print_ISBN

0-7803-0006-8

Type

conf

DOI

10.1109/ICC.1991.162384

Filename

162384