Patent ID: 8705985

Claim:
A method for setting a logic threshold in an optical receiver suitable for detecting a binary optical data signal, said method comprising: a. converting said binary optical data signal, via a photo detector, to a binary electrical signal that is proportional to said binary optical data signal, b. at a previous time said binary electrical signal comprising a previous logic high value (P H ) and a previous logic low value (P L ) in response to said binary optical data signal, said previous P H value and previous P L value having a previous extinction ratio, c. setting a previous logic threshold suitable for distinguishing logic values in said binary electrical signal, or a derivative thereof, d. at a later present time, said binary electrical signal comprising at least one of a present P H value and a present P L value in response to said binary optical data signal, said present high value and present low values having a present extinction ratio, wherein the previous extinction ratio and the present extinction ratio are substantially equal, e. measuring at least one of i. a previous P H value and a present P H value related to said previous and present high value, respectively, and ii. a previous P L value and a present P L value related to said previous and present low value, respectively, f. updating said previous logic threshold to a present logic threshold based on the at least one previous extinction ratio, and at least one of i. the measured previous and present P H value and ii. the measured previous and present P L value.