Optical receiver for regeneration of optical signal

Abstract

An optical receiver includes: a converting unit that converts an optical signal into an electrical signal; an amplifying unit that amplifies the electrical signal; a regenerating unit that regenerates the amplified electrical signal; a correcting unit that performs correction of an error included in the regenerated electrical signal; a monitoring unit that performs monitoring of an optical current flowing through the converting unit; and a control unit that calculates a decision threshold based on a result of the correction and a result of the monitoring.

1 . An optical receiver comprising: 
 a converting unit that converts an optical signal into an electrical signal;    an amplifying unit that amplifies the electrical signal;    a regenerating unit that regenerates the electrical signal amplified by the amplifying unit;    a correcting unit that performs correction of an error included in the electrical signal regenerated by the regenerating unit;    a monitoring unit that performs monitoring of an optical current flowing through the converting unit; and    a control unit that calculates a decision threshold based on a result of the correction and a result of the monitoring.    
   
   
       2 . The optical receiver according to  claim 1 , further comprising a feedback unit that controls a direct current level of a signal output from the amplifying unit by branching a part of the signal to be fed back to the amplifying unit.  
   
   
       3 . The optical receiver according to  claim 2 , wherein the decision threshold is input to the feedback unit.  
   
   
       4 . The optical receiver according to  claim 1 , further comprising: 
 a pre-stage amplifying unit that outputs a signal to the amplifying unit;    a supplying unit that supplies a current to the pre-stage amplifying unit; and    a feedback unit that controls a direct current level of a signal output from the amplifying unit by branching a part of the signal output from the pre-stage amplifying unit to be input to the supplying unit.    
   
   
       5 . The optical receiver according to  claim 4 , wherein the decision threshold is input to the feedback unit.  
   
   
       6 . The optical receiver according to  claim 1 , wherein the decision threshold is input to the regenerating unit.  
   
   
       7 . The optical receiver according to  claim 1 , wherein the control unit includes an analog operating unit.  
   
   
       8 . The optical receiver according to  claim 1 , wherein the control unit includes 
 a controller that outputs a normalized threshold corresponding to the result of the correction; and    a calculator that calculates the decision threshold based on the result of the monitoring and the normalized threshold.    
   
   
       9 . The optical receiver according to  claim 1 , wherein the amplifying unit includes a limiting amplifier.