## 4 Material and Methods
### Implemented Systems and Simulation Parameters  
Figure 10 exhibits the implemented system using Matlab. Since we dealt with digital transmission, binary data were transmitted, and a random binary data generator was used for the data generation. These data underwent the main signal processing techniques  
Figure 9: CFO evaluation process in two cases: Gaussian noise and Gaussian noise with a TU6 fading channel. such as LDPC channel coding, QAM mapping, and OFDM modulation. The signal gathered passed through the Typical Urban 6 channel model, and Gaussian noise was added. As already highlighted in Section 3.3, a CFO was included in the signal according to the simulation cases such as the simulation without a fading channel and the simulation with a fading channel. The reverse operations were then performed at the receiver side. Moreover, the CFO impact was also evaluated when QAM mapping and OFDM were substituted by 2D-NUC mapping and UFMC, respectively. Figure 11 presents the detailed UFMC/NUC-based DVB-T2 system. The process of CFO insertion was performed before the AWGN adding process. The parameters used for all simulations are presented in Table 3. Simulations were carried out assuming perfect channel estimation. While the number of subcarriers and the cyclic prefix were useful in OFDM, in UFMC, the number of subcarriers, the filter length, the sub-band bandwidth, the sub-band number, and the sub-band offset were the useful parameters. Figure 11: UFMC/NUC-based DVB-T2 system: CFO insertion. Figure 10: Light version of the DVB-T2 system: QAM substitution by NUCs and OFDM substitution by UFMC; CFO insertion. Justification for the choice of CFO values  
The normalized CFO values were varied from 0.01 to 0.05. The choice of a maximum CFO equal to 0.05 was justified as follows: The normalized CFO was computed assuming that the transmission frequency was the first DVB-T2 frequency, which is equal to 474 MHz. Indeed, the DTT frequency band varies from 470 MHz to 862 MHz [37]. However, the 790-862 MHz band, called first digital dividend, has been released from Digital Terrestrial Television (DTT) applications. Therefore, the frequency band varying from 470 MHz to 790 MHz is the one used by many countries for DTT deployment [38]. The frequency carrier within this range is equal to 474 MHz. The normalized CFO represents \(\epsilon\) in Equation (6) [34]. This formula is more detailed in Equation (14). This value was gathered by first computing the Doppler shift, as this value depends on the Doppler shift and the OFDM symbol duration, and second, the CFO values. The Doppler shifts were computed using the simulation parameters for the mobile speeds of 50 km/h and 150 km/h. The absolute value of the Doppler shift was computed using Equations (15) and (16) for each value of mobile speed. \[\Delta f_{D_{Max}}=\frac{50}{3.6}\times\frac{474\times 10^{6}}{3\times 10^{8}}= 21.94 Hz \tag{15}\]  
\[\Delta f_{D_{Max}}=\frac{150}{3.6}\times\frac{474\times 10^{6}}{3\times 10^{8}}= 65.83 Hz \tag{16}\]  
\(\Delta f_{D_{Max}}\) values are equal to 21.94 Hz and 65.83 Hz for the mobile speeds of 50 km/h and 150 km/h, respectively. Moreover, the OFDM simulation parameters such as the number of subcarriers \(N_{FFT}=8192\) and the channel bandwidth \(B=8\) MHz were exploited to compute the subcarrier spacing