Peak to Average Power Ratio (PAPR) reduction in OFDM for a WLAN network using SLM technique

Abstract

Orthogonal Frequency Division Multiplexing (OFDM) is a spectrally efficient multicarrier modulation technique for high speed data transmission over multipath fading channels. OFDM modulation schemes offer many advantages for multicarrier transmission at high data rates over time dispersive channels, particularly in mobile applications. One of the main issues of OFDM is high Peak-to-Average Power Ratio (PAPR) of the transmitted signal which adversely affects the complexity of power amplifiers. SeLected Mapping (SLM) technique is one of the promising PAPR reduction techniques for OFDM. This paper analyzes the capability of the existing SLM technique in reducing the effect of Peak-to-Average Power Ratio. The approach is very flexible and works with arbitrary numbers of subcarriers and without restriction on the type of modulation applied in them. The analysis is on a network model designed by WLAN 802.11a standard using MATLAB, a mathematical simulation software tool. As a performance measure for the PAPR reduction, we study the probability that the PAPR of an OFDM data block exceeds a given threshold, which is the Complementary Cumulative Distribution Function (CCDF) of PAPR.