An Efficient PAPR Reduction Scheme for Delta Sigma Modulated Hybrid NOMA System

Abstract

System based on orthogonal frequency division multiplexing with non-orthogonal multiple access represents one of the most promising technology for the next generation of broadcasting and communication systems. One of the main challenges in OFDM-based systems is achieving a high peak-to-average power ratio (PAPR). This paper proposes a novel precoding method, namely Zadoff-Chu matrix transform, for PAPR reduction in OFDM NOMA systems. On top of that, continuous-magnitude OFDM signals require an expensive mixed-signal DAC, and LED drivers need to be modified. Using delta-sigma modulators (DSM), we propose that continuous magnitude OFDM symbols can be converted into signals of LED driver using visible light OFDM systems by introducing ZCT precoded DSM based OFDM NOMA system in this work. This can reduce nonlinear distortion in the DAC and driving circuits due to a high PAPR. We demonstrate that the developed scheme successfully reduces PAPR in a remarkably better way.