A Low-Complexity Companding Transform for Peak-To-Average Power Ratio Reduction in OFDM Systems

The high peak-to-average power ratio (PAPR) feature is one main drawback associated with orthogonal frequency division multiplexing (OFDM) systems. To overcome this problem, many approaches have been presented in the literature, such as the selected mapping technique, the partial transmit sequence technique, the linear nonsymmetrical transform (LNST), and the exponential companding transform (Exp-CT). However, most of them involve high computational complexity. In this paper, we propose a new low-complexity companding transform scheme for PAPR reduction. From computer simulations, the proposed low-complexity scheme can successfully reduce the PAPR value with a lower bit error rate than the Exp-CT scheme and smaller spectrum side-lobe generation than the LNST and Exp-CT schemes. It is useful for physical realization of an OFDM system.