Title :
Simple model of optical amplifier chains to evaluate penalties in WDM systems
Author :
Forghieri, Fabrizio ; Tkach, R.W. ; Favin, D.L.
Author_Institution :
Crawford Hill Res. Lab., AT&T Bell Labs., Holmdel, NJ, USA
fDate :
9/1/1998 12:00:00 AM
Abstract :
A simple model to evaluate the penalty due to amplifier gainshape in a wavelength division multiplexing (WDM) optical system is proposed. The model requires only knowledge of the overall gain of the amplifier chain for all channels and provides signal-to-noise ratio (SNR) penalties for given launched powers. It also provides the input power distribution required for SNR equalization, and the associated SNR penalty, by solving an eigenvalue/eigenvector problem. The penalty predicted by the model agrees well with recent field measurements on a transoceanic cable. The model can also be applied to predict the gainshape of the amplifier chain from a measurement of the output noise spectrum with no input signal. The capacity of a long amplifier chain can thereby be determined from the receiving terminal only
Keywords :
erbium; fibre lasers; laser noise; optical cables; optical fibre networks; submarine cables; wavelength division multiplexing; Er-doped fibre amplifiers; SNR equalization; SNR penalties; WDM systems; amplifier chain; amplifier gainshape; associated SNR penalty; eigenvalue/eigenvector problem; input power distribution; optical amplifier chains; output noise spectrum; overall gain; receiving terminal only; signal-to-noise ratio; transoceanic cable; wavelength division multiplexing optical system; Eigenvalues and eigenfunctions; Optical amplifiers; Power amplifiers; Power distribution; Power system modeling; Predictive models; Semiconductor optical amplifiers; Signal to noise ratio; Stimulated emission; Wavelength division multiplexing;
Journal_Title :
Lightwave Technology, Journal of
