# Analytical Framework of CP-Free Multiuser OFDM System for Coordinated Multi-Point at mmWave
## 3 Simulation Results  
In this section, a MATLAB-based simulation is conducted to evaluate the system performance in terms of BER, PAPR, and PSD. Different types of channel coding and ZF signal detection technique on the performance of CoMP-JT-based downlink mmWave CP-free multiuser OFDM wireless communication systems has been properly investigated. It is verified from [34] that federal communications commission (FCC) rules allowed a 5G BS operating in the millimeter range to emit an effective radiated power (ERP) of up to 30,000 W; further, one of the leading telecommunications equipment company, Huawei, is supporting an antenna port ERP of 65 dBm for their mmWave products [35]. In this simulation study, a transmission power of 5000 W (66.9897 dBm) is considered. Additionally, the current study is carried out with the speculation that the channel state information (CSI) of the mmWave path loss incorporated MIMO Rayleigh fading channel is easily accessible from the receiver and the nature of the flat fading channel coefficients is unaltered during the period of simulation. To understand the work in a better way, it is represented in a concise form using a flow-chart in Figure 4.  
The suggested framework is simulated to derive the system performance by considering the parameters in Table 2. Before presenting simulated results for BER, PAPR, and PSD, a comprehensive idea can be obtained from Table 3 on estimated signal power at both the BS and user end. The presented BER simulation results in Figures 5-8 show the impact of implementing various channel coding under two higher-order digital modulation schemes (16-QAM and 16-PSK) and the ZF signal detection techniques on system performance for each of the four users. In all cases, the simulated CoMP-JT-based downlink mmWave CP-free multiuser OFDM wireless communication system shows improved performance in the case of 16-QAM compared with 16-PSK. It is clearly visible in Figure 5 for user 1 that the system shows better response under the repeat and accumulate (RA) channel coding technique and worst response under the Quasi LDPC channel coding technique in both 16-QAM and 16-PSK higher-order digital modulation techniques. It is observable that the evaluated BER values are 0.0439, 0.002, and 0.3071 in the case of (3,2) SPA, RA, and Quasi LDPC channel coding techniques under 16-QAM, respectively, for a customarily accepted SNR value of \(-5\) dB. At this sort of customarily considered SNR value, the performance of the system using RA channel coding is improved by 13.414 dB and 21.862 dB in comparison with (3,2) SPA and Quasi LDPC channel coding techniques for 16-QAM. In the case of 16-PSK digital modulation, the overall performance of the RA channel coding technique is much better compared with other utilized channel coding techniques. However, a critical observation of the system under 16-PSK depicts that the BER values for (3,2) SPA and RA channel coding techniques are almost identical at 0 dB SNR value. Figure 4: Flow-chart of the simulated work. Figure 6 is for user 2, where it is seen that the estimated BERs under 16-QAM are found to have values of 0.0572, 0.0117, and 0.3394 in the cases of (3,2) SPA, RA, and Quasi LDPC channel coding techniques, respectively, with identical consideration of the SNR value. All these are pointing towards improved performance of the system by 6.892 dB and 14.625 dB in RA compared with (3,2) SPA and Quasi LDPC channel coding techniques. With 16-PSK, it is observable that the BER values evaluated for the case of (3,2) SPA, RA, and Quasi LDPC channel coding techniques are 0.0786, 0.0320, and 0.1960, respectively, which confirms an improvement in the performance of the system by 3.903 dB and 7.871 dB in RA compared with (3,2) SPA and Quasi LDPC channel coding techniques.