Title :
Intermodulation and harmonic distortions of laser diodes with optical feedback
Author_Institution :
Inst. fuer Hochfrequenztech., Tech. Univ. Berlin, Germany
fDate :
11/1/1991 12:00:00 AM
Abstract :
Analytical expressions for the second-order harmonic and the third-order intermodulation distortions of laser diodes with optical feedback are derived. It is shown theoretically and experimentally that optical feedback from the transmission fiber considerably enhances intermodulation and harmonic distortions of laser diodes. Third-order intermodulation distortions up to -15 dBc must be expected for two-tone modulation and low-intensity modulation indexes m≈7% per carrier, which affects the performance of subcarrier multiplexed (SCM) communication systems. To avoid additional distortions the external feedback level must be two orders of magnitudes lower than the critical external feedback level of the laser diode
Keywords :
feedback; intermodulation; laser theory; optical communication equipment; optical modulation; semiconductor junction lasers; DFB laser diode; analytical expressions; external feedback level; laser diodes; low-intensity modulation indexes; optical feedback; second-order harmonic; third-order intermodulation distortions; transmission fiber; two-tone modulation; Charge carrier density; Diode lasers; Equations; Frequency; Harmonic analysis; Harmonic distortion; Intermodulation distortion; Laser feedback; Optical distortion; Optical feedback;
Journal_Title :
Lightwave Technology, Journal of
