Wave Division Multiplexing (WDM)

Wave Division Multiplexing (WDM) combines two, three, and sometime four wavelengths onto a common fiber. WDM uses a multiplexer at the transmitter end to join the wavelengths together and a demultiplexer at the receiver end to split them apart. Typical wavelengths include 1310nm, 1490nm, and 1550nm. A 1590nm wavelength is sometimes used for video control.