A Dynamic Beamforming Technique for Ultraviolet-Based Indoor Communications

This paper presents a novel dynamic transmit beamforming technique for ultraviolet (UV) based indoor communications. The proposed system is able to estimate the user position and orientation on real time basis. The objective of the proposed scheme is to maximize the signal-to-noise ratio (SNR) at the user location, subject to the total power constraint from all the UV sources. This constraint is essential to satisfy the UV radiation safety exposure limit. We develop an algorithm which first estimates the user location and then utilizes a fraction of the total transmitting power to be directed towards the estimated user location to establish a communication link. We maximize the achievable rate for a line-of-sight (LOS) communication link using the dynamic beamforming technique incorporated with localization in UV indoor communications. It is demonstrated through simulations that the proposed scheme is capable of providing a high received signal-to-noise ratio (SNR) at the desired user location.