Title :
Optical modulation depth improvement in SCM lightwave systems using a dissymmetrization scheme
Author_Institution :
CNET, Lannion, France
fDate :
6/1/1994 12:00:00 AM
Abstract :
A scheme is proposed that permits the increase of the rms optical modulation depth (OMD) in SCM lightwave systems, without correlative increase of clipping-induced nonlinear distortion. This scheme is based on the addition to the SCM signal of low-pass filtered pulses, produced in synchronism with the peaks of the SCM signal, in order to prevent the clipping occurring during these peaks. An experiment demonstrating the feasibility is described. An rms OMD improvement of 4 and 5 dB has been obtained for a SCM band of 200-800 and 200-600 MHz, respectively.<>
Keywords :
optical links; optical modulation; subcarrier multiplexing; 200 to 800 MHz; SCM band; SCM lightwave systems; SCM signal; clipping-induced nonlinear distortion; dissymmetrization scheme; low-pass filtered pulses; optical modulation depth improvement; rms OMD improvement; rms optical modulation depth; synchronism; Digital modulation; Frequency modulation; Low pass filters; Nonlinear distortion; Optical fibers; Optical filters; Optical modulation; Optical noise; Optical pulses; Optical transmitters;
Journal_Title :
Photonics Technology Letters, IEEE
