Patent ID: 8103166

Claim:
An apparatus comprising: a polarization-diversity optical hybrid, the polarization-diversity optical hybrid having a first input for receiving a multi-wavelength signal including M sub-channels, each sub-channel at a different wavelength, the optical hybrid having a second input for receiving a reference light source including M continuous-wave references, each continuous-wave reference at a different wavelength that approximates a center wavelength of one of the M sub-channels, the optical hybrid having at least four outputs; at least four Wavelength De-Multiplexing (W-DMUX) filters, each W-DMUX filter having a W-DMUX input, each of the W-DMUX inputs provided a corresponding one of the outputs of the optical hybrid, each W-DMUX filter providing M filtered optical channel outputs; 4M detectors, each detector for converting at least one of the filtered channel outputs into a corresponding electrical signal; and 4M analog-to-digital converters (ADCs), each ADC for converting one of the electrical signals into a corresponding digital signal; wherein M is an integer greater than one.