Performance improvement of OFDM using hybrid PAPR reduction technique

One of the major concerns of Orthogonal Frequency Division Multiplexing (OFDM) systems are its high Peak to Average Power Ratio (PAPR) values. These high PAPR values result in serious degradation in performance when a non-linear power amplifier is employed. The Conventional Partial Transmit Sequence (C-PTS) technique is one of the highly efficient methods for PAPR reduction in OFDM systems. Unfortunately, the number of Inverse Fast Fourier Transform (IFFT) operations employed in C-PTS technique is large and this adds to the computational complexity of the technique. In our proposed Hybrid technique, we have combined the C-PTS technique with interleaving and signal clipping method. The peaks of the OFDM signal are compressed by interleaving the data frame associated with it. All the extra IFFT operations that are required for C-PTS technique are avoided by our proposed method. Signal clipping and filtering result in reducing PAPR values even further. The simulation results show that our proposed hybrid technique achieves better reduction compared to the C-PTS technique at reduced computational complexity.