Active coherent beam combination has been a hot area of research for several years. Particular algorithm module is used to stabilize the phase difference between beamlets, and make them coherent. The phase noise increases with the raising power of laser output. Under low power condition, we simulate the phase noise of high power laser amplifier by the Arbitrary Function Generators (AFGs), and send them to the phase modulators to destabilize the phase, to test the performance of the phase lock algorithm. The experimental results show the feasibility.
In this thesis, the currently feedback control algorithms used in the polarization controller, including
simulated annealing algorithm and gradient algorithm were analyzed. On this basis, a new method of polarization
control feedback algorithm based on fast locating algorithm was proposed to solve the defects of the original algorithm,
such as poor convergence and long time consuming search. It can reduce convergence time and improve the response
speed of the polarization controllers. This new endless polarization control algorithm using 4-plate polarization
controller was proposed and demonstrated. The results showed that the response time of the polarization controller was
less than 1ms. The control of polarization was achieved and the output polarization state was stable while the light
intensity fluctuated less than 2%, which could run endless reset freely.