Visible Light Communication (VLC) is a promising wireless communication technology that utilizes Light Emitting Diodes (LEDs) for high-speed data transmission. However, its performance is significantly affected by temperature variations, which impact the quality factor (Q-factor), signal integrity, and modulation bandwidth. Additionally, frequency-dependent distortions and external noise sources further degrade transmission quality, increasing Bit Error Rate (BER). This study investigates the effect of temperature on the Q-factor at different driver currents (100, 200 and 300 mA) and explores post-equalization techniques to enhance LED modulation bandwidth. An R//C equalization circuit was implemented to compensate for frequency-dependent losses, while a blue optical filter minimized interference and improved the Signal-to-Noise Ratio (SNR). Experimental results indicate that at a driver current of 200 mA and a temperature of 34.8 °C, the highest Q-factor of 14.250 was achieved. Furthermore, an adaptive equalization scheme enabled a 20 Mbps data rate over a 10 cm transmission distance, demonstrating its effectiveness in mitigating signal degradation. The findings highlight the importance of post-equalization in overcoming temperature-induced performance degradation in VLC systems. The proposed approach enhances system stability and reliability, making VLC a viable option for high-speed optical wireless communication under varying thermal conditions.
Download this paper
