K. Rajesh et al, International Journal of Computer Science and Mobile Computing, Vol.3 Issue.5, May- 2014, pg. 562-566 © 2014, IJCSMC All Rights Reserved 562 Available Online at www.ijcsmc.com International Journal of Computer Science and Mobile Computing A Monthly Journal of Computer Science and Information Technology ISSN 2320–088X IJCSMC, Vol. 3, Issue. 5, May 2014, pg.562 – 566 RESEARCH ARTICLE Weighted Mean Scheme for PAPR Reduction of OFDM Signals K. Rajesh 1 , K. Suresh 2 ¹Information Technology & Sri Venkateswara College of Engineering, Chennai, India ²Information Technology & Sri Venkateswara College of Engineering, Chennai, India 1 rajeshkmessenger@gmail.com; 2 ksuresh@svce.ac.in Abstract — In orthogonal frequency division multiplexing (OFDM) system, high peak-to-average power ratio (PAPR) is the main drawback. In this paper, a Weighted Mean scheme is proposed to reduce the high peak- to-average power ratio of the discrete OFDM signal without difficulty in removing the mean weight at the receiver section. In the proposed scheme, Weighted Mean scheme is imposed on every two successive positive and negative discrete OFDM signal point at the transmitter section and original discrete OFDM signal is completely regained without distortion in removing the Weighted Mean at the receiver section. The simulation result shows that bit-error-rate (BER) performance of the Weighted Mean scheme is enhanced compared to both weighted and clipping technique. Keywords— Bit-error-rate (BER); peak-to-average power ratio (PAPR); orthogonal frequency division multiplexing (OFDM); weighted data I. INTRODUCTION OFDM is a bandwidth-efficient signalling scheme for wideband digital communications. OFDM is used for wideband digital communication, which is commonly used for digital television and audio broadcasting as well as broadband Internet access and wireless networking. Orthogonal frequency division multiplexing is a modulation technique for digital multi-carrier modulation that modulates multiple carriers simultaneously. Although their spectra overlap, the transmitted multiple carriers can be demodulated orthogonally. OFDM is a robust against narrowband interference, because such interference affects only a small percentage of subcarriers and it has high spectral efficiency. Even though it has several advantages, the main drawback of OFDM-based systems is the high PAPR of a transmitted signal, which causes a distortion of a signal at the nonlinear high-power amplifier (HPA) of a transmitter and efficiency of the high power amplifier is greatly reduced. Hence, high peak to average ratio must be reduced to avoid signal distortion at the transmitter. To avoid the high PAPR, various techniques have been developed such as clipping and filtering technique [1]-[3]; companding [4], [5]; peak cancellation [6]; coding [7]; tone rejection [8]; partial transmit sequence [9]; weighted [10] and a Survey is presented in [11] which provides reader with a broader understanding of the high PAPR problem. The survey clearly defines the metrics based on which the performance of PAPR reduction schemes can be evaluated. The taxonomy of PAPR reduction schemes classifies them into signal distortion, multiple signalling and coding techniques.