Title :
High quality 64 channel 15 km AM-FDM transmission using low distortion characteristics DFB laser module
Author :
Uno, T. ; Tanabe, M. ; Matsui, Y. ; Ohshima, M. ; Fujito, K.
Author_Institution :
Matsushita Electr. Ind. Co. Ltd., Osaka, Japan
Abstract :
The distortion mechanism of distributed-feedback (DFB) laser modules has not yet been studied extensively. The authors report an additional distortion degradation characteristic, which is caused by the etalon interference effect in a laser module. This effect occurs between two or more reflection facets of the optical components in a module, such as optical lens, polarizers, Faraday crystal, and fiber facet. The calculation results for the second-harmonic distortions (HM2) show that less than 0.1% power reflection from both etalon facets can degrade HM2 up to 50 dB in certain conditions. It is notable that HM2 and HM3 values change periodically against the center wavelength change, and that HM2 and HM3 take two peaks in the free spectral range (FSR) of the etalon cavity.<>
Keywords :
amplitude modulation; distributed feedback lasers; frequency division multiplexing; optical communication equipment; optical links; optical modulation; semiconductor junction lasers; 15 km; 64 channel; AM-FDM transmission; DFB laser module; Faraday crystal; antireflection coatings; distortion degradation characteristic; etalon cavity; etalon interference effect; fiber facet; low distortion characteristics; optical components; optical lens; polarizers; power reflection; reflection facets; second-harmonic distortions; Distributed feedback devices; Fiber lasers; Laser feedback; Laser noise; Optical distortion; Optical fiber losses; Optical fibers; Optical noise; Power lasers; Signal to noise ratio;
Conference_Titel :
Broadband Analog Optoelectronics: Devices and Systems, 1990. Conference Digest., LEOS Summer Topical on
Conference_Location :
Monterey, CA, USA
DOI :
10.1109/BAODS.1990.205498
