A novel approach for reduction of PAPR in OFDM communication

Orthogonal Frequency Division Multiplexing (OFDM) has become the most efficient multi carrier modulation technique for achieving high data rate transmission in wireless communication. OFDM technology possesses various advantages like high spectral efficiency, Immunity against multipath fading and negligible intersymbol interference. However, despite these advantages, OFDM performance has been limited by high Peak Power to Average Power Ratio (PAPR). In this paper, we propose a combined algorithm of Independent Component Analysis (ICA)/Principle Component Analysis (PCA) and Clipping method for reducing the PAPR of OFDM System. Firstly, OFDM signal is processed using ICA or PCA to reduce PAPR, and then further reduction is done by using clipping and filtering method. This constitutes a significant reduction in PAPR without the degradation of bit error rate (BER).

I. Introduction

To meet increased demand for high data rate transmission in wireless communication various digital schemes have evolved. Orthogonal Frequency Division Multiplexing (OFDM) can be considered as a promising modulation technique for achieving high spectral efficiency, negligible Inter Symbol Interference(ISI) and tolerance to multipath delay spread[4]. Now OFDM has emerged as a prominent scheme for digital communication applications such as digital television and audio broadcasting (DAB and DVB-T), DSL internet access, 4G mobile communications, IEEE 802.11 a, IEEE 802.16 and IEEE 802.20[2]. In OFDM, available spectrum is divided into different subcarriers and each subcarrier is modulated with a low data rate stream. The subcarriers are chosen in such a way that they are orthogonal to each other. Orthogonality property of subcarriers in OFDM prevents the use of guard bands thereby eliminating additional overhead.