## 4 Results and Discussion
### Performance Analysis  
The performance of the proposed system is evaluated with BBD precoding without precoding technique. The indoor MIMO-VLC system performances are analyzed in terms of BER with respect to the different SNR. In the case of indoor MIMO-VLC system without precoding, the data transmission from the LED transmitter to PD receiver is analyzed to evaluate the proposed system. The performance of the proposed system is analyzed for three different scenarios.  
Table 3 shows the scenarios considered to analyze the indoor MIMO-VLC system that shows the length, width and height of the room. The performance analysis for the aforesaid three different scenarios are given as follows:  
\begin{table}
\begin{tabular}{c c} \hline \hline \multicolumn{2}{c}{**Parameters of LED Transmitter**} \\ \hline Amount of LEDs per luminary & 60 \(\times\) 60 \\ LED transmitter power & 10 mW \\ Semi angle of transmitter & 15\({}^{\circ}\) \\ \hline \multicolumn{2}{c}{**Parameters of PD Receiver**} \\ \hline FOV of receiver & 15\({}^{\circ}\) \\ PD area & 1.0 cm\({}^{2}\) \\ PD responsivity & 1 A/W \\ PD lens’ refractive index & 1.5 \\ Gain of optical filter & 1.0 \\ Background current & 100 \(\mu\)A \\ Bandwidth factor of noise & 0.562 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Simulation parameters.  
\begin{table}
\begin{tabular}{c c} \hline \hline \multicolumn{2}{c}{**Scenario 1**} \\ \hline Length (\(\lambda\)) & 5 m \\ Width (\(\gamma\)) & 5 m \\ Height (\(Z\)) & 3.5 m \\ SNR range & 10–60 dB \\ \hline \multicolumn{2}{c}{**Scenario 2**} \\ \hline Length (\(\lambda\)) & 4 m \\ Width (\(\gamma\)) & 4 m \\ Height (\(Z\)) & 3 m \\ SNR range & 60–120 dB \\ \hline \multicolumn{2}{c}{**Scenario 3**} \\ \hline Length (\(\lambda\)) & 5 m \\ Width (\(\gamma\)) & 5 m \\ Height (\(Z\)) & 3 m \\ SNR range & 160–260 dB \\ \hline \hline \end{tabular}
\end{table}
Table 3: Scenarios for the analysis of indoor MIMO-VLC system.  
Figures 2-4 shows the BER, throughput and power for scenario 1 of the indoor MIMO-VLC system. From Figures 2 and 3, it can be concluded that the proposed system has less BER and higher throughput due to the utilization of BBD precoding in the data transmission. Additionally, the power consumption of the proposed system during the data transmission is less, when compared to the MIMO-VLC system without precoding technique. For example, the throughput for scenario 1 is 19,242 bps at 70 dB; it is high when compared to the MIMO-VLC system without precoding. The BBD precoding used in the proposed system minimizes errors due to the thermal noise, shot noise and phase noise.  
The BER, throughput and power analysis of proposed system with MIMO-VLC system without precoding is illustrated in Figures 5-7, respectively. From Figures 5 and 6, it can be concluded that the proposed method achieves higher throughput and lesser BER during the data transmission. In addition, the power consumed by the proposed system is less than the proposed system without precoding technique. For example, the proposed system BER of scenario 2 is 0.0  
Figure 4: Evaluation of power for scenario 1.  
Figure 5: Evaluation of BER for scenario 2.  
Figure 6: Evaluation of throughput for scenario 2.  
Figures 8-10 show the BER, throughput and power of scenario 3 for the indoor MIMO-VLC system. From Figures 8 and 9, it can be concluded that the proposed system has less BER and high throughput due to the utilization of BBD precoding in the data transmission. In addition, Figure 10 shows that the proposed system achieves lesser power consumption than the MIMO-VLC system without precoding technique. For example, the BER for scenario 3 is \(6.3\times 10^{-5}\) at 70 dB; it is less when compared to the MIMO-VLC system without precoding. Additionally, the throughput of the proposed system is 26 Kbps at 140 dB; it is high when compared to the MIMO-VLC without any precoding. Due to less BER, the data rate achieved in the receiver is high in the proposed system. The higher data rate achieved in the receiver