Comparative Performance Analysis for Peak-to-Average Power Ratio Reduction in OFDM System Based on the Fractional Fourier Transform Using Selective Mapping and an Active Constellation Extension Technique

—Orthogonal Frequency Division Multiplexing (OFDM) is an attractive modulation technique for transmitting large amounts of digital data over radio waves. One major disadvantage of OFDM is the high peak to average power ratio (PAPR) considered as the main implementation drawback of OFDM system. In this paper, we are discussing about PAPR, which affects the performance and efficiency of Power Amplifier and its influence of utilizing the selective mapping (SLM) technique and Active Constellation Extension (ACE) for PAPR reduction in OFDM systems. The Proposed SLM and ACE techniques for reducing the PAPR are the most promising reduction technique in its non-uniform phase factor for PAPR reduction in OFDM system. In addition, an approximate expression using the complementary cumulative distribution function (CCDF) of PAPR is discussed. The simulated results of comparative analysis demonstrate that OFDMA signals, which have used ACE technique, indeed provide a significant reduction of PAPR in OFDM system.