The number of channels are chosen according to the standards. the more the number of channels, the more some signals fall far from the fiber center, where the dispersion or other characteristics are more appropriate. Also, issues like nonlinear crosstalk are taken into consideration. However, for CWDM, DWDM and WDM the number of channels differ, as the channel spacings are different.
I do not understand your question…are you asking what number of channels is better, or which channel to choose among the transmitted ones to analyze performances?
sir please explain in simple language which of the edfa- wdm system gives a better performance? which should we choose and why? do you mean to say that it depends on choice of dwdm , cwdm systems?
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