Optical device for receiving combs with inter-channel frequency spacing

摘要

The device (D) has demultiplexing units (D0-D2, DM-1) i.e. array waveguide grating, each comprising an input connected to an output of a separation unit (S) for receiving copy of comb, and outputs for delivering demultiplexed optical channels. Outputs of demultiplexing units have central filtering frequencies at each time, where the frequencies are arranged on a grid of optical frequencies spaced regularly at constant gap. The filtering frequencies are offset from each other at a shift value less than the gap. Coherent reception modules are connected to the outputs of the demultiplexing units.