A low complex peak-to-average power ratio reduction in orthogonal frequency division multiplexing systems using a two-dimensional interleaving strategy

摘要

One of the effective peak-to-average power ratio (PAPR) reduction methods in orthogonal frequency division multiplexing (OFDM) systems is the partial transmit sequence (PTS) method in which the input data stream is divided into disjoint subblocks and the subcarriers in each subblock multiplied by predefined phase factors. Consecutive data symbols corresponding to a source/user are often more correlated, so when the corresponding subcarriers are weighted by the same phase factor, a sufficient reduction in PAPR cannot be attained by the PTS algorithm in common subblocks. To solve this problem, in this paper, we propose a new systematic PAPR reduction method based on a two-dimensional subcarrier mapping. Specifically, we scramble/interleave each OFDM symbol based on T-transform to obtain a new set of subblocks which will be multiplied by predefined phase factors. In the proposed method, each one-dimensional symbol sequence is converted to a two-dimensional matrix, and the partitions are formed starting from the main diagonal diameters in the matrix. We present the permutation matrix and reformulate the T-transform technique based on the permutation matrix. Through numerical experimentations, it is shown that the proposed PAPR reduction technique outperforms the previous counterparts. Also, we analyzed our proposed results by aperiodic autocorrelation function (ACF); reducing of ACF side lobes shows that our proposed method cause considerable PAPR parameter reduction respected to other methods.