Patent ID: 8774646
Filing Date: 2014-07-08
Classification: H04B,H04J

Abstract:
1. An apparatus, comprising: an optical coupler having an input and first and second outputs, the input receiving a wavelength division multiplexed (WDM) optical signal, the WDM optical signal including a plurality of optical channels each having a corresponding one of a plurality of wavelengths, the first output supplying a first portion of the WDM optical signal and the second output supplying a second portion of the WDM optical signal; a first photodiode configured to receive the first portion of the WDM optical signal and supply a first electrical signal; an optical hybrid circuit configured to receive at least a part of the second portion of the WDM optical signal; a laser configured to supply a local oscillator optical signal to the optical hybrid circuit, such that the optical hybrid optical circuit supplies first and second optical outputs; an output circuit including second and third photodiodes that receive the first and second optical outputs, respectively, the output circuit supplying a second electrical signal, the output circuit including: a processor circuit that adjusts at least one of a current and voltage of the second electrical signal in response to the first and second digital outputs.