Energy Efficiency of Visible Light Communication using SEE-OFDM

Wireless internet access technology can experience a major revolution through the use of breakthrough technology of Visible Light Communication (VLC) or Li-Fi (light fidelity) which could promise much higher data rates and better security and integrity of the data at the physical layer. There are many challenges being faced when visible light communication is being used resulting in low efficiency of the system. The main purpose of this paper is to endeavour to achieve highest data rate possible in an indoor environment while tackling problems which include loss of energy efficiency as OFDM is made unipolar and real-valued.A novel unipolar scheme called ‘Spectral and Energy efficient’ (SEE-OFDM) is proposed which is compatible with IM/DD wireless systems and is a great candidate for VLC. SEE-OFDM delivered promising results as it doubles the spectral efficiency of unipolar OFDM format. The fundamental idea is to generate multiple signals and sum them; both even and odd subcarriers are transmitted to carry information and the signal remains immune to interference. It is an attractive choice since higher data rates and SNR are gained, with a significant reduction in PAPR relative to conventional ACO-OFDM.