A low-complexity peak-to-average power ratio estimation method for OFDM signals

Abstract

The high peak-to-average power ratio (PAPR) of the output signal for the transmitter is one of the main drawbacks of orthogonal frequency division multiplexing (OFDM) systems. To properly approximate the exact peaks of the continuous-time OFDM signal, L (usually ≥ 4) times oversampling is generally used for the discrete-time OFDM signal in many PAPR reduction schemes. However, the oversampling process increases the computational complexity. In this paper, we propose a low-complexity PAPR estimation method - "peak-search-and- partial-interpolation" (PSPI) scheme - to efficiently estimate the PAPR value for the discrete-time OFDM signal. Instead of doing L times oversampling, the proposed PSPI method interpolates the 2(L-1) neighboring samples of L times oversampling for each searched peak of the original discrete-time OFDM signal. The simulation results illustrate that the proposed PSPI method can achieve well-approximated results as good as those of the scheme with four times oversampling, but with much lower computational complexity. © 2006 IEEE.