A Low Complexity PTS-Based PAPR Reduction Method for the Downlink of OFDM-NOMA Systems

Orthogonal frequency division multiplexing (OFDM) based non-orthogonal multiple access (NOMA) systems can considerably increase the attainable data rate and spectral efficiency in novel communication systems. High peak-to-average power ratio (PAPR) is one of the main issues in OFDM-based systems. It makes high-power amplifier (HPA) work in the non-linear region and degrades system performance. Partial Transmit Sequences (PTS) based methods are one of the prominent schemes to reduce the PAPR value. However, they have high computational complexity, and they mostly degrade the system’s Bit Error Rate (BER) performance. In this paper, a low complexity PTS-based method, utilizing the dummy sequence insertion (DSI) technique and cyclic shift sequence (CSS) PTS, is proposed to overcome the previous limitations. Using numerical simulations, we will demonstrate that the proposed method outperforms similar ones in terms of PAPR reduction and BER performance with less computational complexity.