Minimizing the PAPR for FBMC/OQAM Signals Using Enhanced-PTS with Low Complexity Search

Abstract

The filter bank multicarrier with offset quadrature amplitude modulation (FBMC/OQAM) scheme has recently become a focus of interest for many scholars and researchers. Despite its impressive advantages over Orthogonal Frequency Division Multiplexing (OFDM), the FBMC/OQAM system exhibits high Peak-to-Average Power Ratio (PAPR) which could plague its performance if it is not properly managed. In this paper, we proposed a PAPR reduction scheme that improves the Partial Transmit Sequence (PTS) to an enhanced PTS (EPTS), then employs a low complexity search to determine the optimal combination of phase factors. In the enhanced PTS, the FBMC/OQAM data blocks are partitioned into sub-blocks by taking into account their overlapping arrangement, then a segmentation operation is performed to the overall overlapping partitioned data blocks in order to form several segments of sub-blocks. After that, the segments are optimized consecutively by applying a phase factor search approach. Referred to as enhanced PTS with iterative flipping (EPTS-IF), the proposed scheme optimizes consecutively the segments of sub-blocks by employing Iterative Flipping approach. The PAPR reduction performance and the computational complexity of the proposed scheme have been evaluated through computer simulations and theoretical analysis which revealed a significant PAPR reduction gain of approximately 30.48%, and at a low computational cost.