Simulation and analysis of Stochastic Parallel Gradient Descent control algorithm for coherent combining

A new phase locking method for Master Oscillate Power Amplifier (MOPA) coherent combining system is proposed in this paper. The algorithm called Stochastic Parallel Gradient Descent (SPGD) control is adopted to correct piston errors and generate the feedback signals. The capability of this algorithm for coherent combining is demonstrated by simulation, and the relative parameters which directly influence the algorithm's convergence are also analyzed.

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