Flexible Nonlinear Companding Transform for Reducing PAPR of Multi-carrier Signals

An efficient nonlinear companding transform (NCT) scheme is proposed for reducing the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signals. The proposed new scheme transforms the Gaussian-distributed signals into the specified statistics form based on a piecewise function. By choosing the companding coefficients, it enables more design flexibility in companding form so that a favorable trade-off between PAPR and the bit error rate (BER) performance can be achieved. Comparing with conventional PAPR reduction techniques, the proposed NCT-based scheme with proper coefficients can reduce PAPR efficiently as well as improve BER performance simultaneously.