Physical Layer Security Under the Effect of Dimming in Visible Light Communications

Visible Light Communication (VLC) is a promising option for 6G wireless systems to increase performance and provide a high-speed data rate compared to radio frequency (RF). Dimming control is one of the most important aspects to be considered in VLC. It is very critical for the future of VLC to adjust the brightness of the light source to be used in communication and to ensure that the light source, with a changing brightness, maintains the desired communication performance due to the situation and environment. This work proposes a novel pilot-aided estimation method for channel and dimming coefficients in spatial modulation (SM)-VLC systems. As a result, in the VLC system running with the PLS algorithm, while the information transmitted to the legal user is received with an excellent BER performance, it is observed that the BER performance of the eavesdropper is around 0.5, which is the worst possible situation for the illegal user.