A Linear Programming Approach for PAPR Reduction in OFDM Systems

Abstract

Peak-to-average-power ratio (PAPR) is a key design concern of an OFDM system as it determines the system's power efficiency. Clipping is a simple and efficient way of reducing PAPR. A suboptimal recursive clipping and filtering (RCF) method was proposed in [5] to reduce PAPR. This paper presents an alternate RCF approach which selects an error (clipping) vector that minimizes the peaks in both I-and Q-channels while satisfying some time and frequency domain distortion bounds. We formulate the design problem as a constrained linear programming (CLP) problem and extend it to include the tone-reservation option. Like the RCF method, our approach does not need side information and incurs no data rate loss. Since the error vector used in RCF has not been optimized, our approach offers improved PAPR reduction. It also provide tradeoff between PAPR reduction and bit error rate (BER) degradation.