Tunable Wavelength Add/Drop Multiplexer Based on Integrated Optic Devices

摘要

A tunable wavelength add/drop (t-WDM) device utilizes a multiwavelength input (which serves as a data input port), a low loss optical circulator or an optical coupler, a wavelength division de-multiplexer which splits the input multi-wavelength data stream into itsd individual components, a modified multi-channel DOS, a telecommunications grade optical fiber, and a wavelength multiplexer for adding optical data channels. The input multi- wavelength data stream from a network is sent to a wavelength de-multiplexer where it is demultiplexed into individual wavelengths which are applied to an array of Y-branch digital optical switching devices controlled by a computer. If a specific wavelength is to be dropped, it is diverted towards a branch of a given switch which has a fiber pig tail attached. If a specific wavelength is to be sent through (neither dropped or added) then the signal is diverted towards a mirrored end of the Y-branch, where it is reflected back towards the wavelength de-multiplexers to the circulator and goes out the output end of the t-WADM. If a wavelength slot' has ben vacated by a dropping channel then a new data stream may be added in that slot.