###### Abstract
The BER decreased in response to increased anisotropy levels in various directions. Moreover, the performance of an optical wireless communication system operating in anisotropic oceanic turbulence is better than that when operating in isotropic oceanic turbulence. Due to the numerous effects of beam propagation in the ocean, many techniques are used to improve the efficiency of the entire UWOC system. To compensate for the effect of alignment error on the coupling efficiency of single-mode fiber, [PERSON] et al. designed a fiber coupler with a degree of freedom coupling structure and used a variable-gain stochastic parallel gradient descent algorithm to find the optimal alignment attitude [18]. [PERSON] et al. used the intermediate frequency signal as the feedback control signal, which improved the mixing efficiency of the system [19]. The corner detection method and the optical flow method were used by [PERSON] et al. to calculate the optical flow displacement based on two consecutive frames. The results show that the method is feasible and can eliminate noise accurately [20]. Considering the impact of oceanic turbulence on UWOC, some excellent schemes have been employed to decrease the scintillation index. Considering the impact of oceanic turbulence on UWOC, some excellent schemes have been employed to decrease the scintillation index, including the utilization of multiple-input and multiple-output [21; 22; 23], different beam types at the transmitter [24; 25] and larger aperture diameters [26]. Aperture averaging, i.e., expanding the aperture diameter of the receiver, has proven to be a useful method for enhancing the communication performance of optical beams propagating in turbulence. Approximate expressions for the aperture averaging of scintillation in atmosphere environment were derived by Churnside [27]. It was concluded that if the aperture diameter is larger than the spatial size that produces irradiance fluctuations, the receiver will average the fluctuations, thereby reducing the scintillation index. [PERSON] et al. [28] compared the performance of wireless optical communication systems with single-aperture and multi-aperture receivers under different turbulent conditions. The conclusion is drawn that under moderate turbulence, a single large aperture diameter is more conducive to obtaining good performance than multiple aperture diameters, while using multiple aperture diameters is more advantageous than using a single large aperture diameter under strong turbulence. Furthermore, increasing the aperture diameter is also a good way to improve communication performance in oceanic turbulence. The averaging aperture effect has a significant impact on the UWOC system, which has been studied in detail in [29]. In [30; 31], the scintillation index of an optical wave in both anisotropic and isotropic turbulence was greatly decreased with the aperture averaging effect. Although the influence of wave shapes, aperture averaging and turbulence parameters on UWOC systems has been extensively studied, the impact of the inner and outer scales of turbulence has not been well examined. Motivated by this, [PERSON] et al. analyzed the scintillation index of a Gaussian laser beam containing both inner and outer scales effects on a ground-space slant path under moderate-to-strong atmospheric turbulence [32]. A theoretical irradiance fluctuation expression based on new spectra of plane and spherical waves in weak turbulence was derived in [33], which proved that the scintillation expression in atmospheric turbulence can fit well for oceanic turbulence under a small inner scale. [PERSON] et al. further studied the scintillation index of a Gaussian beam through a non-Kolmogorov maritime atmospheric turbulence channel with the aperture averaging effect and discussed the influence of the inner scale of the maritime turbulence [34]. It was revealed that the scintillation index of the Gaussian beam increased with increasing inner scale and decreasing receiver aperture diameters.