A Study on Audio Signal Quality Assessment in Visible Light Communication

Visible Light Communication (VLC) has been considered a supplementary technology to conventional Radio Frequency (RF) communication systems, offering a multitude of advantages. Several research studies have demonstrated the feasibility of employing VLC technology for reliable audio communication. The primary objective of this paper is to examine the quality of the analog audio signal through the utilization of intensity modulation and direct detection (IM/DD) scheme. The low-cost transceiver based on OpenVLC capes has been exploited to perform a preliminary study and evaluate the performance of an analog short-range IM/DD VLC system. To the best of our knowledge, no previous research has thoroughly examined the quality of the audio signal transferred via VLC. The evaluation of audio quality is conducted based on the following parameters: Total Harmonic Distortion (THD), Intermodulation Distortion (IMD), Signal-to-Noise Ratio (SNR), and Signal-to-Noise And Distortion (SINAD). Furthermore, the impact of daylight illuminance levels on the mentioned parameters has also been analyzed, considering three distinct values of amplitude and bias voltage. The obtained results indicate that VLC can facilitate the transmission of audio signals with satisfactory and faithful quality, with an achieved THD level below 1% in the best-case scenario.