Wavelength division multiplexing WDM

Figure 10. SPR dual-channel sensors based on wavelength division multiplexing (WDM) of sensing channels. WDM of sensing channels by means of altered angles of incidence (upper). WDM of sensing channels by means of a high refractive index overlayer (lower) .

While there are other multiplexing/demultiplexing schemes, the two most common are time division multiplexing (TDM) and wavelength division multiplexing (WDM). 

SEMICONDUCTOR OPTICAL AMPLIFIERS have received less attention in the literature than amplifiers using optical fibers as the gain medium. Fiber amplifiers, including Erbium-doped fiber amplifiers and Raman amplifiers are currently transforming the world of optical fiber telecommunications as they become incorporated as line amplifiers in high-capacity wavelength-division multiplexed (WDM) transmission systems. However, despite the dominance of fiber amplifiers in the telecommunications marketplace, semiconductor optical amplifiers continue to show potential for application in a range of... 

Many optoelectronic devices based on NLO properties of materials have been fabricated in the last years and their importance in integrated optics is growing more and more. For example they can be used in dense wavelength division multiplexers (WDM), laser cavities, spectrometers, reflectors and Alters in optical interconnects. 

Figure 17-11. Setup used to measure the net opticalgain of an erbium-doped waveguide amplifier (EDWA). Signal and pump beams are mixed in a wavelength-division-multiplexing (WDM) component and, after the amplifier, separated by another WDM component. An optical spectrum analyzer is used to detect the amplification bandwidth.

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