A Theoretical Analysis of Li-Fi: A Last Mile Solution

A last mile technology that is identified to potentially relieve the digital divide in emerging markets, and especially relevant in rural communities, is light fidelity (Li-Fi). Li-Fi can take advantage of current infrastructures (lighting) to distribute the internet to local communities in these areas. Li-Fi last mile solutions do not require large investments in implementing traditional infrastructures such as fibre or copper which are challenging, expensive or unpractical in these areas. Li-Fi uses light in the visible spectrum and propagates through free space—two important factors when considering an infrastructure that already exists in many rural communities. Information can be modulated onto these light signals (carriers) and be detected and demodulated with photodetectors. Since the (carrier) frequency of the light signal is very high (in the THz range), there are little bandwidth limitations when transmitting information using light, a distinct advantage of Li-Fi that offers numerous benefits. The principles of operation (including an introduction into Li-Fi channel modelling), benefits and limitations, as well as potential Li-Fi applications, are researched in this chapter and delivered to the reader as methodological principles of light-based communications.