# Reducing PAPR with Low Complexity Filtered NOMA Using Novel Algorithm
###### Abstract  
Filtered Non-Orthogonal Multiple Access (F-NOMA) is a multi-carrier wave form and is considered a suitable contender for 5G radio. Peak to average power ratio (PAPR) is regarded as a major hurdle in the NOMA wave form because it hampers the efficiency of the power amplifier of the NOMA transmitter. In this study, a novel selective mapping (SLM) algorithm is used to minimize the PAPR of the NOMA. The conventional SLM increases the intricacy of the structure, and the projected SLM algorithm is applied to the transmitter part of the F-NOMA. Furthermore, we evaluate the performance of SLM on F-NOMA for 16, 64, and 256-Quadrature Amplitude Modulation (QAM) transmission methods. The parameters such as Bit Error Rate (BER), PAPR, power spectral density (PSD), and complexity are estimated and compared with different transmission patterns. The simulation outcomes of the work reveal that the optimal PAPR can be achieved by selecting the sub-block (S) and phase rotation elements (Ps). PAPR in F-NOMA achieves 1 dB gain in different QAM transmissions and its saving performance is 70.07%; however, complexity increases with an increase in modulation order. p 2022  
31 July 2022  
5 August 2022  
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**1. Introduction**  
The enhancement of cellular communication is taking place all around the world, and there is an exponential demand for wireless applications. The integration of 5G with various machineries such as the Internet of Things (IOT), Cognitive Radio (Cr), massive MIMO, and wearable small devices is happening all the time [1]. Better quality of service (QoS), faster data, latency (1 ms), and more efficient bandwidth utilization are among the demands that the 5G rollout is expected to meet [2]. Multi-carrier waveforms will determine the success of 5G. Currently, the OFDM waveform is utilized in 4G. Several multi-carrier waveforms such as NOMA, FBMC, and UFMC are proposed for 5G radio; however, PAPR is a common concern in all advanced waveforms [3]. The increase in PAPR diminishes the performance of the system and it is considered one of the major constraints in 5G. The PAPR issue in OFDM is overcome by applying PAPR reduction algorithms [4]. However, due to the differences in the structure of the 4G and 5G waveforms, the algorithms used in 4G cannot be applied to the 5G waveform. In recent years, PAPR reduction algorithms havebeen designed for 5G waveforms [5]. In this work, we evaluate the performance of the SLM algorithm for the 16-QAM and 64-QAM transmission methods. In [6], the SLM algorithm is designed for the UFMC waveform. The reduction in PAPR is obtained by generating an ideal phase vector of complex UFMC symbols. The proposed article reveals a substantial enhancement in PAPR performance. The authors in [7] introduced a novel hybrid PAPR technique for 5G wave forms. Their studied scheme is centered on the permutation of PTS and BFOA and concluded that the presented arrangement efficiently lowers the PAPR and reduces the complexity of the framework. In [8], the authors compared the PAPR performance for filtered OFDM and conventional OFDM. The PTS is used in the F-OFDM waveform to lower the PAPR and it is seen that the F-OFDM outperforms the conventional OFDM waveform framework. The authors introduced a novel Gray-PFPTS algorithm for OFDM and F-OFDM waveforms [9], which efficiently reduces the PAPR and intricacy. The model consequences confirm that the enactment of the projected process is superior to the prevailing systems. In [10], the PAPR of the FBMC wave is lowered by applying DCT and DST algorithms. The outcomes of the simulation show that the simulation shows that the proposed method effectively obtains a gain of 5 to 10 dB. In [11], the authors investigated the PAPR and latency of 5G wave forms. The QRM-MLD method is projected to increase the efficiency of the structure. The simulation results show an improved PAPR performance of the framework.