Title :
Performance of single-electrode 1.5-μm DFB lasers in noncoherent FSK transmission
Author :
Fishman, Daniel A.
Author_Institution :
AT&T Bell Labs., Holmdel, NJ, USA
fDate :
7/1/1991 12:00:00 AM
Abstract :
The author reports the results of an investigation of the performance of single-electrode 1.5-μm DFB (distributed feedback) lasers in 1.7-Gb/s noncoherent frequency-shift-keyed (NC-FSK) transmission. Sixteen commercial laser transmitters were characterized in terms of FSK transmission sensitivity, eye-margin, chromatic dispersion penalty and pattern dependence. Using amplitude-shift-keying (ASK) performance as a baseline, FSK is shown to outperform ASK when dispersion is present, while ASK is slightly better with no dispersion. FSK transmitters with commercial single-electrode DFB lasers are shown to provide an attractive alternative to ASK in dispersion limited systems. The FSK degradations mainly result from an inadequate FM modulation index and a thermal-FM index manifested as a pattern length dependence
Keywords :
digital communication systems; distributed feedback lasers; frequency shift keying; optical communication equipment; semiconductor junction lasers; transmitters; 1.5 micron; 1.7 Gbit/s; FM modulation index; FSK degradations; FSK transmission sensitivity; amplitude shift keying performance; chromatic dispersion penalty; commercial laser transmitters; dispersion limited systems; eye-margin; noncoherent frequency shift keyed transmission; pattern length dependence; single electrode distributed feedback lasers; thermal-FM index; Amplitude shift keying; Chirp modulation; Erbium-doped fiber amplifier; Erbium-doped fiber lasers; Filters; Frequency modulation; Frequency shift keying; Laser modes; Optical losses; Transmitters;
Journal_Title :
Lightwave Technology, Journal of
