PAPR Reduction Analysis of OFDM signals in DVB-T system using SLM and PTS techniques

Abstract

DVB-T uses very popular multicarrier modulation system such as OFDM and the OFDM signals in DVB-T has highPeak to Average Power Ratio (PAPR). One way to reduce the high PAPR is by using efficient techniques. In this research, we analyse the PAPR reduction of OFDM signals using SLM and PTS techniques. The input considered for DVB-T system is video signal taken from internet. The simulations of these techniques are carried out using MATLAB. Keywords: OFDM, DVB-T, SLM, PTS, QAM, PAPR, Techniques I. INTRODUCTION Digital terrestrial television (DTT) is also called as Digital Video Broadcasting-Terrestrial (DVB-T) television is currently an efficient communication technology for broadcasting television (TV) signals[1]. The European digital television ETSI EN 300 744, standard is DVB-T, for the terrestrial transmission to fixed, portable, and mobile receivers [2]. The specification of framing structure, channel coding and modulation, for digital terrestrial broadcasting is provided by DVB-T Standard. DVB-T system refers, to the source coding of data, audio signals and video signals, the channel coding and the technique for the transport of the DVB-T signals by means of all type of transmission media. In DVB-T, the OFDM is used to transmit 2k and 8k mode carriers over AWGN, Rician and Rayleigh Channel, the received signal at the receiver is corrupted. The corrupted received signal is manipulated in terms of SNR values (ranging from 0db to 16dB) and modulation techniques (4-QAM, 16-QAM 64-QAM and 128-QAM). OFDM modulation [3] is attractive technique for high data rate transmission, since it can cope with frequency selective fading channel. The Fig.1 gives the DVB-T System Physical Layer block diagram. In DVB-T the most serious problem of OFDM is high Peak to average power ratio (PAPR) which causes degradation of system performance. So reduction of PAPR is very much needed in order to utilize the benefits of OFDM for DVB-T applications. Various PAPR reduction techniques are proposed in literature for OFDM system and in this research we have considered the most widely used techniques such SLM and PTS [4] [5].