Novel Linear Companding Transform Design Based on Linear Curve Fitting for PAPR Reduction in OFDM Systems

Peak-to-average power ratio (PAPR) reduction is an important issue for orthogonal frequency division multiplexing (OFDM) systems. In this letter, a novel method of continuous piecewise linear curve fitting (CPLCF) is first proposed to design linear companding transforms (LCTs) for PAPR reduction in OFDM systems. From given nonlinear companding transforms (NCTs), this method can derive corresponding LCTs with similar performance and much lower complexity. The constrained optimization problem is formulated, and parameter selecting method is provided. By employing the CPLCF method, a novel LCT scheme, named ANC-LCF, is derived from newly proposed adjusted nonlinear companding (ANC) prototype. Simulation results verify the validity of the novel design method and the performance superiority of the proposed ANC-LCF scheme.