A New Low-Complexity Trellis Shaping Design Based on Clipping for PAPR Reduction in BICM-OFDM System

In order to mitigate the high peak-to-average power ratio (PAPR) problem of orthogonal frequency-division multiplexing (OFDM) signals, various PAPR reduction techniques have been studied. In this work, we focus on the trellis shaping (TS) which controls a signal by utilizing the structure of convolutional code at the transmitter. TS has flexibility of design and shows high PAPR reduction capability without causing any nonlinear distortion. However, the major drawback of the conventional TS is its computational complexity required for metric calculation in the codeword search associated with PAPR reduction. In this paper, we propose an alternative approach that makes use of signal clipping to generate a replica of the reference symbols in the Viterbi algorithm so as to reduce the complexity of the metric calculation. Through extensive simulations in the framework of BICM-OFDM, we demonstrate the effectiveness of the proposed approach as well as its cost in return for significant reduction of the transmitter complexity.