Water surface wave turbulence is one of the factors affecting the performances of underwater optical wireless communication (UOWC) systems. In our research, a phase-conjugate beam was used to correct the beam distortion and enhance the communication performances when a system is subject to surface wave turbulence. The phase-conjugate beam was generated by a phase-conjugate mirror (PCM), and a turbulence generator was used to generate surface wave turbulence in the experiment. We calculated the beam centroid distribution and the results showed that the phase-conjugate beam had a better propagation performance than the distorted beam at the different water depths. The root mean square (RMS) of the beam centroid for the phase-conjugate beam was 11 times less than that for the distorted beam, which meant that the phase-conjugate beam could effectively correct the beam drift. We further investigated the scintillation index and the signal-to-noise ratio (SNR); the results showed that the phase-conjugate beam was able to reduce the scintillation and an obvious improvement in SNR could be obtained. This research has the potential to be applied in UWC.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9756247PMC
http://dx.doi.org/10.1007/s12200-022-00039-yDOI Listing

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