Title :
Intermodulation distortion for a hybrid AM-VSB/digital system using a 1.55-μm laser and an optical amplifier
Author :
Freeman, P.N. ; Dutta, N.K.
Author_Institution :
Lucent Technol., Bell Lab., Murray Hill, NJ, USA
Abstract :
The performance of a hybrid AM-VSB/BPSK optical fiber transmission system utilizing 1.55-μm distributed feedback (DFB) laser and Er doped optical amplifier is presented. A BPSK modulated 2-MHz pseudorandom digital channel is substituted for one of the AM channels in a 60-channel CATV system and optically transmitted using a directly modulated 1.55-μm DFB laser. The intermodulation distortion effects with and without optical amplification were studied. No degradation of the AM channels is observed unless the modulation depth of the BPSK channel is increased far beyond the level required for successful transmission to the point where laser clipping effects become significant.
Keywords :
amplitude modulation; cable television; distributed feedback lasers; electro-optical modulation; fibre lasers; intermodulation distortion; optical fibre networks; phase shift keying; semiconductor lasers; 1.55 mum; 2 MHz; 60-channel CATV system; AM channels; BPSK modulated MHz pseudorandom digital channel; DFB laser; Er doped optical amplifier; directly modulated /spl mu/m DFB laser; distributed feedback laser; hybrid AM-VSB/BPSK optical fiber transmission system; hybrid AM-VSB/digital system; intermodulation distortion; laser clipping effects; modulation depth; optical amplifier; optically transmitted; Digital systems; Distributed feedback devices; Fiber lasers; Intermodulation distortion; Laser feedback; Laser noise; Optical amplifiers; Optical distortion; Semiconductor optical amplifiers; Stimulated emission;
Journal_Title :
Photonics Technology Letters, IEEE
