With the ever-increasing demand for more mobile bandwidth and higher data transfer rates, expansion into the Terahertz spectral range is inevitable. Modern Wi-Fi technologies (2.4 GHz and 5 GHz) theoretically support data rates up to only a few Gbps. A newly emerging technology, Light Fidelity (Li-Fi) provides communication with potentially Tbps rates through LED lighting. One unique benefit of Li-Fi is that it can be used simultaneously for illumination and high-speed, secure (line-of-sight) communication. Li-Fi would be best utilized in conjunction with Wi-Fi and mobile LTE networks as it is more suitable for one-way short range communication due to relatively high power needed for the lighting source.
Combining wavelength division multiplexing (WDM) and frequency division multiplexing (FDM), this project focused on realizing a high-speed optical communication link for a cost comparable to a Wi-Fi router. By processing data using a microcontroller with an Ethernet connection, a 52 Mbps link was demonstrated [three frequencies (n=3) for each of the primary colors (Red, Green, Blue) — a total of nine (3n) channels]. Data transfer rates up to 486 Mbps were shown to be viable with this three-color three-frequency system.
Integrating data processing and multiplexing/demultiplexing functionalities on a single chip would eliminate the bottleneck imposed by the microcontroller clock speed. Additionally, this Li-Fi system can be scaled up by adding a yellow LED, which would also improve the quality of white light, and by adding more carrier frequencies. With these improvements, Li-Fi stands to provide high-speed communications through LED lighting.https://scholarscompass.vcu.edu/capstone/1110/thumbnail.jp
