Optical GFDM: an improved alternative candidate for indoor visible light communication

Abstract

This paper proposes generalized frequency division multiplexing (GFDM) for indoor visible light communication (VLC). GFDM is a flexible multi-carrier scheme that allows engineering in both time and frequency domain, therefore, making GFDM suitable for various 5G applications. In the literature, different types of optical orthogonal frequency division multiplexing (O-OFDM) have been proposed for VLC including direct current offset optical OFDM (DCO-OFDM), asymmetrically clipped optical OFDM (ACO-OFDM), Flip-OFDM, etc. O-OFDM can provide high data rate, but it suffers from the problem of the high peak-to-average power ratio (PAPR) which causes clipping distortion, reduces the illumination-to-communication conversion efficiency and affects the lifetime of the LED. The proposed optical GFDM (O-GFDM) scheme for VLC is analyzed for various performance metrics against the O-OFDM counterpart. The analytical expression for symbol error rate (SER) of O-GFDM is derived and simulation results based on PAPR, SER and subcarrier frequency shift tolerance validate the improved performance of the proposed O-GFDM scheme. It is found that one of the variants of the proposed scheme has better spectral efficiency and lower power consumption compared with O-OFDM counterpart. As GFDM is being considered for 5G wireless systems, it is expected that the GFDM-based VLC system will very well gel with next-generation wireless systems to offer seamless services and will provide greater flexibility using software-defined networking.