摘要 |
<p>A configurable add/drop optical system is disclosed for demulitplexing, adding and/or dropping closely spaced channels carrying optically encoded data. A composite optical signal having data channels corresponding to centre wavelengths lambda 1, lambda 2, lambda 3, lambda 4, ... lambda n are separated into two composite optical signals of first of which comprises data channels corresponding to centre wavelengths lambda 1, lambda 3, ... lambda n and a second which comprises data channels corresponding to centre wavelengths lambda 2, lambda 4, ... lambda n-1, by passing the composite signal through an interleaver circuit in a demultiplexing mode of operation. Two such interleaver circuits are optically coupled to one another and controllable, tunable Bragg gratings disposed therebetween are used to route demultiplexed signals along preferred signal paths. <IMAGE></p> |