Title :
On the validity of using CW tones to test the linearity of multichannel M-QAM subcarrier multiplexed lightwave systems
Author :
Wu, Ming-Chia ; Chiang, Pi-Yang ; Way, Winston I.
Author_Institution :
Dept. of Commun. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan
fDate :
4/1/2000 12:00:00 AM
Abstract :
We investigate the validity of using multiple continuous-wave (CW) tones as the signal source to test the linearity of a multichannel M-ary quadrature-amplitude-modulation (M-QAM) subcarrier multiplexed lightwave system. We consider the following representative optical fiber system nonlinearities: 1) laser clipping and 2) the combined effect of laser frequency chirp and fiber dispersion. Our results show that if all orders of nonlinear distortions (NLDs) in a signal bandwidth are included in the total NLD power, the error caused by replacing M-QAM signals with CW tones can be within measurement uncertainty.
Keywords :
measurement uncertainty; nonlinear optics; optical fibre dispersion; optical fibre networks; optical fibre testing; quadrature amplitude modulation; subcarrier multiplexing; CW tones; fiber dispersion; laser clipping; laser frequency chirp; linearity; measurement uncertainty; multichannel M-QAM subcarrier multiplexed lightwave systems; multichannel M-ary quadrature-amplitude-modulation subcarrier multiplexed lightwave system; multiple continuous-wave tones; nonlinear distortions; optical fiber system nonlinearities; signal bandwidth; signal source; total NLD power; Chirp; Fiber lasers; Frequency; Laser noise; Linearity; Nonlinear distortion; Optical fiber dispersion; Optical fiber testing; Optical fibers; System testing;
Journal_Title :
Photonics Technology Letters, IEEE
