Visible Light Communications Using Commercially Available Fluorescent Fibers as Optical Antennas

The use of fluorescent optical antennas in visible light communications (VLC) can enhance the transmission performance due to their multiple functions of optical filtering, light concentration and collecting light from a wide range of incident angles. One convenient way to create an optical antenna is by using commercially available fluorescent fibers. In this paper, we introduce a new antenna structure made of two bent fluorescent fibers and study its performance in a white light-emitting diode (LED)-based VLC system. We show that, since the fluorophore doped into the selected fiber only absorbs the blue light emitted from the gallium nitride (GaN) LED rather than the yellow light converted from the phosphor coating, it can result in a high modulation bandwidth. Also, by placing two bent fibers in an intersecting way, the receiver becomes omnidirectional. More importantly, our experimental results show that, when the illuminance at the receiver is a typical indoor lighting level, the receiver incorporated with this new fluorescent antenna can result in a much higher transmission data rate compared to the case when no antenna is used.