## 4 Simulation Results and Analysis  
This section uses Monte Carlo (MC) simulation to verify the accuracy of the theoretical analysis results and examines the impact of core parameter selection on system performance. Assuming that the UWOC link operates in the water quality of the nearshore coast, its extinction coefficient satisfies the require \(c_{0}=0.305\ m^{-1}\). The typical values of other important parameters required for system simulation are shown in Table 2 Further assuming that the average signal-to-noise ratio of the two-hop links is equal, that is, \(\mu_{r}=\rho_{r}=\overline{\gamma}\), the threshold noise is set \(\gamma_{th}=2\)dB. Figure 2 shows the theoretical calculation values and MC simulation values of the average outage probability of the RF-UWOC hybrid double hop relay transmission system under different RF link parameter values as a function of the average SNR \(\overline{\gamma}\). The solid line in the figure represents IM/DD detection, while the dotted line represents heterodyne detection (HD), the dashed line represents the corresponding asymptotic value curve, and the asterisk represents the MC simulation value. At this point, the coefficient values for the Generalized K distribution channel fading of the first hop RF link are set as follows \((m,k)\): \((0.5,1.9),(1.0,1.9),(2.0,2.6)\)[21] (Correspond to the pink, blue, and red curves in the figure respectively). where the horizontal and vertical distances between UAV and R: \(r=~{}900\) m, \(\rm{h}=2000\) m, and the weak pointing error \(\xi=4.0\) of the second hop UWOC link (corresponding to jitter deviation \(\sigma_{s}=25\) cm, receiver radius \(r_{a}=30\) cm, and beam width \(w_{z}=30\) cm); underwater transmission distance \(d=20\) m; ocean turbulence scintillation index \(\sigma_{1}^{2}=0.1074\). From the simulation results in Figure 2, it can be seen \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Figure** \\ \hline Horizontal distance between UAV and R & \(300/900/3000\) m [18] \\ Vertical distance between UAV and R & \(400/2000/4000\) m [18] \\ The generalized K-fading parameter of RF link, \(m,k\) & \(0.5,1.9/1,1.9/2,2.6\)[6,12] \\ Parameters related to atmospheric path loss calculation, & \(-1.5,3.5,200,10\)[19] \\ \(a_{1},b_{1},a_{2},b_{2}\) & \(6^{\circ}\)[10] \\ Full width beam divergence angle, \(\theta_{1/e}\) & \(6^{\circ}\)[10] \\ correction factor, \(T\) & \(0.13\)[10] \\ Receiver aperture diameter, \(D_{R}\) & \(10\) cm [10] \\ Underwater transmission distance, \(d\) & \(10/15/20\) m [20] \\ Jitter deviation, \(\sigma_{s}\) & \(25/35/65\) cm [16] \\ Receiver radius, \(r_{a}\) & \(30\) cm [16;18] \\ Ocean turbulence scintillation index, \(\sigma_{l}^{2}\) & \(0.1074/0.2066/0.4548\)[16;18] \\ GGD shape parameter, \(c\) & \(3\)[16] \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Main parameters of RF-UWOC system performance simulation RF-UWOC. that under the condition of fixed parameters of the UWOC link (underwater transmission distance \(d=20\) m, ocean turbulence intensity \(\sigma_{l}^{2}=0.1074\), and pointing error \(\xi=4.0\)), whether the system adopts IM/DD detection or heterodyne detection receiving schemes, the performance of outage probability will continue to improve due to the increase in coefficient values in the RF link. This is due to the value of m that reflects the intensity of small-scale Nakagami fading in the RF link, and the smaller the value of m, the closer the small-scale fading is to the weak. Rician fading of the direct path signal. The \(k\) value is inversely proportional to the average power of the random variable that characterizes large-scale shadow fading, and the larger the \(k\) value, the weaker the shadow effect. All of these indicate that generalized K-fading has a significant impact on the outage probability performance in RF links.