# BDCOA: Wavefront Aberration Compensation Using Improved Swarm Intelligence for FSO Communication
## 4 Conclusions  
In this research, BDCOA is developed to compensate for the WA in the SLAO over the free space optical communication. BDCOA is used to select optimum control signals for the actuators in the DM. The BM and DM incorporated in the BDCOA are employed to avoid suboptimal solutions and to improve search space efficiency to ensure balance among exploration and exploitation while searching for the control signal for the DM. The optimum control signals from BDCOA are used to enhance phase compensation in DM by reducing the phase distortion and improving the FSO's performances. Therefore, the optimization of dynamic control signals for DM based on the BDCOA is used to upgrade the coupling efficiency. Moreover, the reduction in phase distortions is achieved by effectively  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Performances**} & \multirow{2}{*}{**Methods**} & \multicolumn{4}{c}{**Iterations**} \\ \cline{3-5}  & & **50** & **100** & **150** & **200** \\ \hline SR & AMFSPGD [28] & 0.83 & 0.88 & 0.89 & 0.89 \\  & BDCOA & 0.89 & 0.90 & 0.93 & 0.93 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Comparison of BDCOA for Scenario 2.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Performances**} & \multirow{2}{*}{**Methods**} & \multicolumn{4}{c}{**Iterations**} \\ \cline{3-6}  & & **100** & **200** & **300** & **400** & **500** \\ \hline \multirow{3}{*}{RMS} & SA-SPGD [27] & 1.65 & 0.9 & 0.45 & 0.2 & 0.15 \\  & OBAFS [29] & 1.7 & 0.42 & 0.42 & 0.41 & 0.41 \\  & BDCOA & 1.49 & 0.36 & 0.35 & 0.15 & 0.12 \\ \hline \multirow{3}{*}{Coupling efficiency} & SA-SPGD [27] & 0.77 & 0.785 & 0.795 & 0.798 & 0.8 \\  & OBAFS [29] & 0.87 & 0.93 & 0.93 & 0.93 & 0.93 \\  & BDCOA & 0.89 & 0.94 & 0.94 & 0.94 & 0.95 \\ \hline \multirow{3}{*}{SR} & OBAFS [29] & 0.66 & 0.83 & 0.86 & 0.86 & 0.86 \\  & BDCOA & 0.69 & 0.86 & 0.91 & 0.91 & 0.91 \\ \hline \multirow{3}{*}{BER} & SA-SPGD [27] & 6.30 \(\times\) 10\({}^{-10}\) & 1.99 \(\times\) 10\({}^{-10}\) & 1.58 \(\times\) 10\({}^{-10}\) & 1.41 \(\times\) 10\({}^{-10}\) & 1.25 \(\times\) 10\({}^{-10}\) \\  & BDCOA & 5.21 \(\times\) 10\({}^{-10}\) & 1.71 \(\times\) 10\({}^{-10}\) & 1.49 \(\times\) 10\({}^{-10}\) & 1.23 \(\times\) 10\({}^{-10}\) & 1.07 \(\times\) 10\({}^{-10}\) \\ \hline \hline \end{tabular}
\end{table}
Table 3: Comparison of BDCOA for Scenario 1.  
selecting optimum control signals using BDCOA, which leads to advancement of the peak intensity and SR in time-varying phenomenon. Therefore, the simulations confirm that BDCOA offers superior outcomes compared to SA-SPGD, AMFSPGD, and OBAFS. The RMS of BDCOA for 500 iterations is 0.12, which is less than the SA-SPGD and OBAFS. Moreover, the BER of BDCOA for 500 iterations is 1.07 \(\times\) 10\({}^{-10}\), which is less than SA-SPGD. In the future, a novel optimization technique can be used to further enhance the WA compensation with the mitigation of routing error in FSO communication.  
The paper investigation, resources, data curation, writing--original draft preparation, writing--review and editing, and visualization were done by S.S.K. and N.G.S. The paper conceptualization, and software, were conducted by A.K.G. and V.Y.S. The validation and formal analysis, methodology, supervision, project administration, and funding acquisition of the version to be published were conducted by P.B.D. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
No new data were created or analyzed in this study. Data sharing is not applicable to this article.  
The authors declare no conflicts of interest.