Energy-Efficient Friendly Jamming for Physical Layer Security in Visible Light Communication

This work studies an energy-efficient jamming scheme for enhancing physical layer security in visible light communication (VLC). We consider a VLC system where multiple LED luminaries are deployed together with a legitimate user (i.e., Bob) and passive eavesdroppers (i.e., Eves). In such a scenario, the closest LED luminary to Bob serves as the transmitter while the rest of the luminaries act as jammers transmitting artificial noise (AN) to possibly degrade the quality of Eves' channels. A joint design of precoder and AN is then investigated to maximize the energy efficiency (EE) of the communication channel to Bob while ensuring a certain amount of AN power to confuse Eves. To solve the design problem, we make use of a combination of the Dinkelbach and convex-concave procedure (CCCP), which guarantees to converge to a local optimum.