A Non Uniform DFT-Spread Constellation Reforming Method for PAPR Reduction of OFDM Signals

In this paper, a Non uniform DFT-spread constellation reforming method is proposed for reduction of peak power to average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) system. The key idea of the proposed method is to generate virtually 3-PSK (V3PSK) by reforming quadrature phase shift keying modulation (QPSK). In this reforming modulation constellation point arranged in such way that one of the symbol is comes at origin to get benefit of DFT spreading. When the virtual QPSK constellation is employed with the conventional selected mapping (C-SLM) methods in OFDM systems, called as the V-SLM methods in this paper, Theoretical analysis and simulation results show that the virtual QPSK could reduce PAPR and also it is less complex than the conventional SLM methods.