An investigation of the effects of dynamic human obstacle movement on the performance of indoor visible light communication systems

Human obstacles pose a significant challenge for visible light communication (VLC) systems, causing substantial signal attenuation and performance degradation. This study examines the performance of an indoor Visible Light Communication (VLC) system in the presence of dynamic human obstacles using the Random Waypoint model (RWP). An analysis of the system's performance is conducted with a regular arrangement of light-emitting diodes 3 and 6 LEDs in a straight-line and rectangular design, respectively. The received power was calculated in the absence of obstacles and compared with the presence of obstacles. The intensity profile of blockage was measured for both homogeneous and heterogeneous blockage densities. The analytical equation for the blocking probability was derived, and the probability that obstacles would block the line-of-sight signal from all LEDs was calculated. The results align with the simulation results, confirming the validity of the analytical approach. The received power profile shows a reduction in received power at blockage spots, and the received power diminishes as the number of human obstacles increases. The 6-LED arrangement outperforms the 3-LED configuration in terms of the higher and lower number of blockages while using the same total power from transmitting LEDs. In addition, a comparison table was prepared with previous relevant research that used 4 and 8 LEDs; the purpose of this assessment was to clarify the subtle differences in system performance and the quality of the signal reception. Average receiving power of 1.09 dBm was achieved with 6 LEDs and 6 homogeneous human obstacles, whereas 0.44 dBm was acquired with 8 LEDs and the same intensity of obstacles, proving that 6 LEDs are more effective. That being said, the 4 and 8 LED scenarios work better when faced with heterogeneous obstacles. The proposed analysis is crucial for designing a VLC-based indoor communication system, allowing easy configuration changes, cost-effectiveness, and improved energy allocation using 3 or 6 LEDs.