Review of Non-Linear Transform based Techniques to Reduce the PAPR in OFDM Systems

Abstract

Orthogonal Frequency Division Multiplexing (OFDM) is a spectrum efficient multicarrier modulation scheme for high speed communication systems. OFDM provides robustness against multipath fading channels, but is sensitive to nonlinear effects due to the high Peak-to-Average Power Ratio (PAPR) of the transmitted signal. The reduction in PAPR is desirable in order to obtain power efficiency and to increase BER performance. This paper explores efficient Non Linear Transformation (NLT) algorithms for optimizing the PAPR of the OFDM signals. The proposed techniques avoid the use of additional Inverse Fast-Fourier Transform (IFFT) as compared to Selective Level Mapping (SLM) and Partial Transmit Sequence (PTS) and hence reduce the computational complexity. NLT schemes do not require the transmission of Side Information (SI) to the receiver, which provides better bandwidth utilization