Repetition Code Subblocking for Partial Transmit Sequence OFDM

Partial transmit sequence (PTS) is a proven technique to reduce the peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) systems. It achieves significant PAPR reduction without distortion, but the high computational complexity of multiple Fourier transforms is a problem in practical systems. In this paper, we consider this problem and use intermediate signals within a decimation in frequency (DIF) radix FFT to formulate the OFDM symbols. This enables us to exploit the periodic autocorrelation function (ACF) of the vectors in the PTS subblock partitioning. To improve the PAPR, we use repetition codes (RCs) in the subblocking for the PTS radix FFT. Our approach significantly decreases the computational complexity while providing comparable PAPR reduction to ordinary PTS (O-PTS). Numerical results are given which confirm our analysis.