## 5 Analysis of Simulation Results
### Experimental Verification  
The experimental platform illustrated in Figure 8 was built in a cube space with length, width, and height of 0.8 m, to further verify the feasibility of the antenna selection algorithm based on the Pearson coefficient in practical application scenarios. On the experimental platform, the space of the bottom surface 0.8 m \(\times\) 0.8 m was divided into several areas at intervals of 0.1 m, and six LED light sources (RCW) with a power of 5 W were arranged on the top. Two PDs (LXD33 MK) were arranged on the receiving plane, with the divided area as a reference positioning point, and the average value of the multiple illuminations of the light source in the PD was considered the RSS date.  
Figure 7: Bit-error rate of OGSMP-MIMO system based on Pearson coefficient under different modulation orders.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Number of Active** & **Number of Receiving** & **Modulation** & **Antenna Selection** \\
**Antennas \(N_{a}\)** & **Antennas \(N_{r}\)** & & **Algorithm** \\ \hline
2 & 6 & 2 PAM &
\begin{tabular}{c} Pearson \\ selection \\ \end{tabular} \\ \hline
2 & 6 & 4 PAM &
\begin{tabular}{c} Pearson \\ selection \\ \end{tabular} \\ \hline
2 & 6 & 8 PAM &
\begin{tabular}{c} Pearson \\ selection \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table}
Table 3: Parameter information table.  
Assuming that there are two PD terminals, the coordinates are PD1 (0.8, 0.15, 0.35) and PD2 (0.8, 0.25, 0.35); there are four LEDs, and the coordinates are LED1 (0.2, 0.2, 0.8), LED2 (0.2, 0.4, 0.8), LED3 (0.2, 0.6, 0.8), LED4 (0.6, 0.2, 0.8), LED5 (0.6, 0.4, 0.8), and LED6 (0.6, 0.6, 0.8); the number of active antennas at the transmitting end \(N_{a}=2\), and the actual antenna combination of OGSMP-MIMO chooses eight types from fifteen. Combined with the actual experimental platform, it can be determined that there are eight types of illuminances received by different PDs from different LEDs, which can be expressed by Equation (9) as  
\[\begin{array}{l}P_{b}=\frac{1}{10^{6}}\sum\limits_{u=1}^{10^{6}}\sum\limits _{\begin{subarray}{c}u=1\\ \hat{u}\
eq u=1\end{subarray}}^{10^{6}}P(x_{u}\rightarrow\hat{x}_{u})e(u,\hat{ u})\\ \hskip 14.226378 pt+\frac{1}{10^{6}}\sum\limits_{u=1}^{10^{6}}\sum\limits_{ \begin{subarray}{c}u=1\\ \hat{u}\
eq u=1\end{subarray}}^{10^{6}}P(x_{u}\rightarrow\hat{x}_{u})\frac{ \log_{2}L}{2}\\ \hskip 14.226378 pt+\frac{1}{10^{6}}\sum\limits_{u=1}^{10^{6}}\left(1-\prod \limits_{\begin{subarray}{c}u\
eq u=1\end{subarray}}^{10^{6}}P(x_{u} \rightarrow\hat{x}_{u})\right)\log_{2}LP(y_{u})\end{array} \tag{28}\]  
According to Equations (11) and (28), the set of Pearson coefficients is  
\[\rho=\left\{\begin{array}{l}\rho_{1,2}=0.9872,\rho_{1,3}=0.8570,\rho_{1,4}=0. 7808,\rho_{1,5}=0.8593,\rho_{1,6}=0.7205\\ \rho_{2,3}=0.8170,\rho_{2,4}=0.7542,\rho_{2,5}=0.8177,\rho_{2,6}=0.9459,\rho_{ 3,4}=0.9395\\ \rho_{3,5}=0.9468,\rho_{3,6}=0.8669,\rho_{4,5}=0.9452,\rho_{4,6}=0.8115,\rho_{ 5,6}=0.9256\end{array}\right\} \tag{29}\]  
According to Equation (30), the actual activated antenna combination is  
\[N_{c}=\left\{(1,2)\ (3,5)\ (2,6)\ (4,5)\ (3,5)\ (5,6)\ (3,6)\ (1,5)\right\} \tag{30}\]