Bakkas et al.  proposed and investigated Palm Clipping, a novel clipping method based on hyperbolic cosine. The authors used computer simulations to test and analyze its performance concerning PAPR and bit error rate by altering the Clipping Ratio and modulation techniques. The obtained findings reveal that depending on the kind of modulation, a gain of 7 to 9 dB in terms of PAPR reduction are feasible. Furthermore, in terms of PAPR and BER, the approach provides a potent alternative that may be employed as a PAPR reduction tool for OFDM-based systems.
Sarowa et al.  highlighted some of the main strategies for mitigating the unfavorable consequences of the PAPR problem to make the OFDM system more operationally efficient. For the 'Haar' and 'Db8' wavelets, simulation findings reveal that wavelet-based OFDM beats FFT-based OFDM systems by more than 2 dB. Furthermore, considerable reductions in PAPR are achieved using the suggested hybrid strategies i.e., wavelet OFDM + clipping technique. The suggested hybrid system is further examined using various modulation approaches, and it is discovered that using a Haar wavelet hybrid with a companding technique over 16QAM yields significantly improved PAPR results. The wavelet OFDM may be used with other PAPR reduction approaches to improve performance even more.
Lakshmmi and Kanmani  produced OFDM symbols using Offset QPSK as the modulation mechanism, analyzed the peak power and peak-to-average power ratio, then used the proposed strategy to minimize it. The signal distortion category included the lossy coding approach. MATLAB was used to run the simulation. The simulation results of the suggested technique have been addressed, as well as the amount of decrease obtained in the peak to average power ratio and the amount of the bit error rate.
Al-Jawhar et al.  used The PTS approach to minimize the F-OFDM system's high PAPR value. The performance of this system was then compared to that of the OFDM system. Furthermore, for both PTS and non-PTS systems, additional significant aspects were considered and analyzed for instance frequency localization, bit error rate, and computational. The simulation findings demonstrated that, when compared to OFDM, F-OFDM based on PTS achieved greater levels of PAPR, BER, and OOBE performance. Using the PTS technique moreover, does not influence F-BER OFDM's performance.
A partial transmits sequence strategy based on adaptive particle swarm optimization has been proposed by Hosseinzadeh Aghdam et al. . Besides, to reduce computational complexity, the suggested technique looked for the best combination of phase rotation parameters in a short amount of time. The suggested strategy greatly lowered the PAPR and computational complexity, according to the experimental findings.
Mesri et al.  illustrated the partial transmit sequence technique to lower the PAPR in an orthogonal frequency division multiplexing system. Regardless of its benefits, the PTS
The approach is regarded computationally costly owing to the use of several Inverse fast Fourier transforms (IFFT) and the necessity for extensive analysis to determine the ideal phase factor. The key aim was thus to remove the IFFT blocks. A surprising method was employed, which was mostly based on analyzing the available data in random-access memory. Furthermore, the least PAPR value is computed and its associated address is accurately established; this address is the side information to be given to the OFDM receiver to retrieve the users' actual data. Furthermore, the efficiency of the new-PTS method's so-called complexity reduction is highlighted to reduce the number of searches required to get the greatest PAPR performance, which considerably reduced computational complexity overhead. As a result, the numerical analysis and comparison investigation revealed that the suggested PTS system provided overall excellent performance in terms of both bit error rate and PAPR reduction.
Al-Jawhar et al.  introduced a novel low complexity method (Gray-PF-PTS) based on a special mapping rule that combined the Gray code with the left feedback shift register operation. According to the numerical results, the Gray-PF-PTS method greatly reduced computational complexity while preserving PAPR reduction performance when compared to the standard PTS approach. The PAPR, bit error rate, and power spectrum density (PSD) characteristics of OFDM and F-OFDM systems based on the Gray-PF-PTS method, have also been used to explore OFDM and F-OFDM systems.
In his study, Akurati et al.  offered a new hybrid SLM-companding strategy to improve PAPR reduction. Nonlinear companding approaches such as Logarithmic Rooting Companding (LogR) and Tangent Rooting Companding (TanhR) reduced the PAPR from 9.8 dB to 3.6 dB and 6.2 dB, respectively. It also improved system efficiency and minimized the need for complicated hardware. The suggested method's findings are stated; consequently, it may be applied in impending 5G wireless communications systems.
Jawhar et al.  presented an analytical assessment of the standard PTS approach and its variations in three areas: frequency-domain, modulation stage, and time-domain. Over 26 modified PTS techniques were assessed for their ability to increase the performance of PAPR reduction and computational complexity level. Although the DSI-PTS methodology has lower computational complexity than the other frequency domain techniques, the CO-PTS method decreases system computational complexity more than the other modulation-stage methods, according to the data.
Furthermore, in time-domain approaches, the GPW-PTS technique has a low computational cost while maintaining a high PAPR rating. The rows exchange-interleaving PTS technique is the optimum solution for minimizing the PAPR, as per mathematical findings value in the frequency domain while retaining a low level of complexity. The cooperative PTS technique outperformed the modulation stage approaches in PAPR reduction and computing complexity, whereas the cyclic shift sequence PTS method exceeded the time domain methods in PAPR reduction and computing complexity.
Timoshenko et al.  shared their experience with creating signals that would be used in the 5G standard on USRP-2943R. The possible alternatives for lowering the signal's peak factor while raising out-of-band emissions were disclosed. When novel signal generating strategies were used, there was a chance to win. Thus, a loss of just 8 dB in out-of-band emissions as compared to traditional UFMC and FOFDM was still improved by 20 decibels than classic OFDM.
Kumari  introduced a unique wavelet-based OFDM model intending to improve orthogonality and spectral efficiency via the use of different modulation methods. The use of wavelet-based OFDM was remarkable in that it requires no spectral efficiency, and the absence of the cyclic prefix improved bandwidth efficiency as bandwidth expands simultaneously. Finally, the wavelet-based OFDM communication model outperformed the standard FDM communication model in terms of BER. The simulation results demonstrated the usage of wavelet-based OFDM rather than DWT-based OFDM in LTE, as well as a comparison of wavelet-based OFDM with DFT-based OFDM.
The self-adaptive multi-population differential evolution algorithm was used by Hocine et al. . He suggested a suboptimal PTS technique (SAMDE). By evolving each sub-population of individuals through several generations, the self-adaptation of control parameters and structured population managed high-quality solutions with little processing cost.
Sengar and Bhattacharya  discussed various critical elements and offered mathematical scrutiny, including the distribution of the PAPR employed in OFDM systems. SLM and PTS, two signal scrambling techniques, were being investigated to reduce PAPR; both of these have the potential to result in significant reductions in PAPR. In terms of minimizing PAPR, the PTS approach outperformed the SLM method.