Patent ID: 7738796
Filing Date: 2010-06-15
Classification: H01S,H04B

Abstract:
1. A method for controlling a laser, the method comprising: generating a data signal; generating a test signal having a level commensurate with a noise level; modulating a laser bias current with both the test signal and the data signal to produce a modulated laser output; generating a modulated laser signal from the modulated laser output; multiplying the modulated laser signal by a sine function of the test signal to generate a first product; squaring the first product to generate a first squared product; multiplying the modulated laser signal by a cosine function of the test signal to generate a second product; squaring the second product to generate a second squared product; adding the first squared product and the second squared product to generate an extracted test signal; determining an average value of the extracted test signal; calculating a laser bias current adjustment from the average value of the extracted test signal; and applying the calculated laser bias current adjustment to the laser bias current.