PTS-Based Radix FFT for PAPR Reduction in OFDM Systems

A radix FFT-based technique for reducing the peak-to-average power ratio (PAPR) of an orthogonal frequency division multiplexing (OFDM) signal is presented. The authors use intermediate signals in radix decimation in time (DIT) or frequency (DIF) FFT algorithm for subblock partitioning in the partial transmit sequence (PTS) technique. It is shown that DIF achieves low multiplicative complexity in generating PTSs compared to that with DIT and the same PAPR reduction. In addition, high radix FFT algorithms provide better PAPR reduction performance per stage with less multiplicative complexity compared with low radix algorithms.