An all-fiber multiwavelength add-drop multiplexer

Wavelength-division multiplexed (WDM) transmission systems require optical filters to multiplex or demultiplex different wavelength channels. One type of element useful in optical networks is the add-drop multiplexer (ADM) filter. We have assembled a three-wavelength ADM node, composed entirely of passive fiber components. This node can simultaneously add or drop three wavelength channels. The ADM uses four 3-dB fiber couplers, a fiber Bragg reflection filter, and four fiber biconic taper filters.