  The multi-dithering method has been well verified in phase locking of
polarization coherent combination experiment. However, it is hard to apply to
low repetition frequency pulsed lasers, since there exists an overlap frequency
domain between pulse laser and the amplitude phase noise and traditional
filters cannot effectively separate phase noise. Aiming to solve the problem in
this paper, we propose a novel method of pulse noise detection, identification,
and filtering based on the autocorrelation characteristics between noise
signals. In the proposed algorithm, a self-designed window algorithm is used to
identify the pulse, and then the pulse signal group in the window is replaced
by interpolation, which effectively filter the pulse signal doped in the phase
noise within 0.1 ms. After filtering the pulses in the phase noise, the phase
difference of two pulsed beams (10 kHz) is successfully compensated to zero in
1 ms, and the coherent combination of closed-loop phase lock is realized. At
the same time, the phase correction times are few, the phase lock effect is
stable, and the final light intensity increases to the ideal value (0.9 Imax).
