| 摘要 |
In an optical communications system employing a Wavelength Division Multiplexing (WDM) scheme, a demultiplexer such as an Arrayed Waveguide Grating (AWG) can be used. It is known that AWGs are susceptible to wavelength drift as the temperature of the AWG changes. Wavelength drift causes channels to overlap which results in cross-talk between adjacent channels. Consequently, the present invention provides a control loop apparatus and method for detecting and compensating for the presence of cross-talk between adjacent channels in a communications system. To this end, a first and second signal from an AWG (12) are processed by a combinatorial logic unit (60) in order to detect the presence of the second signal in the first signal, thereby detecting the presence of cross-talk. <IMAGE> |
