# Palm Date Leaf Clipping: A New Method to Reduce PAPR in OFDM Systems
## 5 Simulation Results
### Comparative Study
#### 5.3.2 PAPR and BER Comparison with SLM Variants  
In this subsection, we compare our proposal method with SLM and its variants. In [8], the author proposes a new SLM based on the Genetic Algorithm SLM (GA-SLM); this method is compared with the SLM technique based on conversion matrices (CM) and a genetic algorithm (CMSLM) in terms of  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Method** & **PAPR Value** & **PAPR Gain** \\ \hline Normal OFDM & 10.67 & - \\ RS (Random Search) [15] & 7.98 & 2.69 \\ IPTS [15] & 7.22 & 3.45 \\ PSO-PTS [16] & 7.08 & 3.59 \\ GA-PTS [17] & 6.65 & 4.02 \\ Palm Clipping (CR = 7 dB) & 6.40 & 4.54 \\ HGA-PTS [15] & 6.13 & 4.85 \\ Palm Clipping (CR = 6 dB) & 5.83 & 4.27 \\ OPTS (Exhaustive search) [15] & 5.82 & 4.84 \\ Palm Clipping (CR = 5 dB) & 5.00 & 5.67 \\ \hline \hline \end{tabular}
\end{table}
Table 4: PAPR comparison at CCDF \(=10^{-3}\) of Palm Clipping with Partial Transmit Sequence (PTS) variants with \(w\) = 4 and \(v\) = 8. IPTS: Iterative flipping PTS, PSO-PTS: Particle Swarm Optimization Partial Transmit Sequences, GA-PTS: Genetic Algorithm Partial Transmit Sequences, HGA-PTS: Hybrid Genetic Algorithm PTS, OPTS: Optimal PTS.  
Figure 19: CCDF at \(10^{-3}\) of the PC method with a CR of 5, 6, and 7 dB compared with Partial Transmit Sequences (PTS) and its variants, where \(w\) = 4 and \(v\) = 8, \(N\) = 64, with the 16-QAM modulation.  
the PAPR and BER. Figures 20 and 21 present the CCDF and BER, respectively, of the proposed method compared with the new GA-SLM, CMSLM, and the classical SLM. The following parameters apply:  
* \(w=4\) (Phase rotation factors {+1, -1, -j, +j});
* \(M=32\) (Sub-blocks number);
* \(D=32\) (Genetic algorithms: population size);
* \(I=30\) (Genetic algorithms: number of generations or iterations).  
Figure 20 presents the CCDF of our method with the obtained result in [8]. As shown in this figure, the proposed PC method has the same result as the GA-SLM: when CR is equal to 6 dB, we  
Figure 21: BER performance of the proposed method compared with SLM and its variants with \(N=64\), and the modulation 16-QAM over the AWGN channel.  
Figure 20: CCDF of the proposed method compared with the Selective Mapping Technique (SLM) and its variants.  
achieve a reduction of 6 dB. On the other hand, the BER performance presented in Figure 21 shows that the proposed method has the same performance in terms of BER. In the case CR = 5 dB, we can achieve a good reduction with a loss of 1 dB in BER. According to the results in the figure, our method has the same result in terms of PAPR at CCDF = \(10^{-3}\), and it also has the same result in terms of BER. Therefore, in the case of CR = 5 dB, we have the best gain with a loss of about 1 dB in terms of the BER.  
According to the simulation results and summarized results in Table 5, we notice that our method, when CR is less than 5 dB, has the best reduction in terms of the PAPR with a degradation in BER. Therefore, the Palm Clipping method has the same performance when CR = 6 dB. We recommend choosing a value between 6 and 7 dB in order to achieve the same result as compared with other SLM methods in terms of the PAPR and BER.  
The Palm Clipping method achieves good results for some Clipping Ratios with the best performance in terms of BER. From this point of view, we conclude that our method is not complex (no iteration required to find the minimum PAPR) and does not need side information.