<title>Wavelength Division Multiplexing</title>

Abstract

The evolution of fiber optic technology has provided an alternative multiplexing technique called wavelength division multiplexing (WDM). In WDM, each channel is optically modulated onto a light source of a distinct wavelength. All of the wavelengths are then focused onto a single fiber by a wavelength multiplexer device. At the receiving end, the composite optical signal is spectrally filtered or dispersed into its constituent wavelengths by a demultiplexer, and each channel is detected by a photodetector.