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DOE OSTI · 22375929

A high-speed, high-efficiency phase controller for coherent beam combining based on SPGD algorithm

Huang, Zh M·Liu, C L·Li, J F·Zhang, D Y
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Abstract

A phase controller for coherent beam combining (CBC) of fibre lasers has been designed and manufactured based on a stochastic parallel gradient descent (SPGD) algorithm and a field programmable gate array (FPGA). The theoretical analysis shows that the iteration rate is higher than 1.9 MHz, and the average compensation bandwidth of CBC for 5 or 20 channels is 50 kHz or 12.5 kHz, respectively. The tests show that the phase controller ensures reliable phase locking of lasers: When the phases of five lasers are locked by the improved control strategy with a variable gain, the energy encircled in the target is increased by 23 times than that in the single output, the phase control accuracy is better than λ/20, and the combining efficiency is 92%. (control of laser radiation parameters)

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSALGORITHMSBEAMSCONTROLEFFICIENCYFIBERSKHZ RANGE 01-100LASER RADIATIONLASERSMHZ RANGE 01-100STOCHASTIC PROCESSES

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Huang, Zh M, Liu, C L, Li, J F, Zhang, D Y. 2014-04-28. A high-speed, high-efficiency phase controller for coherent beam combining based on SPGD algorithm. https://doi.org/10.1070/qe2014v044n04abeh015230

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