Minimizing the Peak-to-Average Power Ratio of OFDM Signals Using Differentially Encoded Subcarriers

Wireless technologies have gradually become more and more involved in everyday life. An Orthogonal Frequency Division Multiplexing (OFDM) is an attractive multi carrier modulation technique for wireless transmission systems. OFDM has many advantages immunity to impulse interference, robustness to channel fading, high spectral density, resistance to multipath, much lower computational complexity. The major drawback of OFDM is signal suffers a high Peak to Average Power Ratio (PAPR), a high PAPR easily makes the signal peaks move into the non-linear region of the RF power amplifier which causes signal distortion. In this paper we analyze PAPR reduction of OFDM system using a technique that exploits the principle of differential encoding of subcarriers. The effectiveness of proposed technique is evaluated through extensive computer simulations and complementary cumulative distribution function (CCDF) is obtained as a function of number of modulations and subcarriers.