## 2 Configuration and Design of the Proposed UWB-MIMO Antenna
### Modeling and Characterization of the MAVA Combined with MTM Cells  
The findings of the proposed UWB-MIMO antenna's integration with ten components of a modified SRR MTM are provided in this section. The optimum dimensions and properties of the MTM structure are shown in Tables 2 and 3. Figure 12 shows the proposed antenna integrated with MTM components in both simulated and manufactured prototypes, as well as the measurement setup for the constructed antenna. Each unit cell was added with space of almost 4 mm which is less than a quarter wavelength at the center frequency. The MTM arrays are located without any disorientation initially. Then they were periodically rotated by 90 degrees. This was inspired by the fact mentioned above. It was also inspired by the quasi-random solution was proposed in [70] to improve the performance of random metamaterial structures. Random metamaterial structures could potentially be used as RF wave filters or frequency selective surfaces (FSS) for specific frequency-dependent applications. This was done under the hypothesis that performance of each local random element may improve if each element is perpendicular to the incident wave, such as in many periodic metamaterial simulations. It was used to improve the radiation characteristics of antennas like gain after integration depend on their interactions. Moreover, it is also helpful structure if an experiment needed a signal transmitted or received with random fluctuations in the pattern based on direction [70]. The antenna's overall size increased by 6.5 mm in the y direction after the MTM components were added. Next, the proposed antenna is loaded with a staircase meander \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Dimensions (mm)** \\ \hline \(m_{1}\) & 4.50 \\ \hline \(m_{1}\) & 1.50 \\ \hline \(m_{W}\) & 0.27 \\ \hline \(S\) & 0.50 \\ \hline \(a_{m2}\) & 1.5 \\ \hline \(a_{m1}\) & 1.15 \\ \hline \(b_{m2}\) & 1.8 \\ \hline \(b_{m1}\) & 1.4 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: MTM structure dimensions. Figure 12: The final MAVA combined with the MTM: (**a,b**) the simulated structure, (**c,d**) the fabricated prototype (t, \(W_{s}=15\) mm). \begin{table}
\begin{tabular}{c c c} \hline \hline
**Parameters** & \(\epsilon_{r}\) & \(\mu_{r}\) \\ \hline \multirow{2}{*}{Operating BW (GHz)} & 3.2–9, 9.6–13, 13.2, 14–17.5, & 3.1–3.3, 7–10, 12.5–13.5, \\  & 19–26.5, 27.5–30 & 13.8–14, 17.5–18.5, 23.5–27.5 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: The characteristics of the MTM structure. line near to the Ant 1 to improve the BW and shift it to lower band as well as could create a resonance at 3.8 GHz. So that means the lower 5G band coverage is achievable, too [71; 72; 73; 74]. The MAVA antenna's simulated reflection coefficient and transmission coefficient findings at each step of the design are shown in Figures 13 and 14. The researchers found that the final design of the antenna has a working BW of 4.9-40 GHz and a resonance of 3.8 GHz. Additionally, at the full working BW, the simulated transmission coefficient is less than \(-22\) dB. Figure 15 indicates the proposed MAVA's simulated and measured S\({}_{11}\) and S\({}_{21}\). A Performance Network analyzer: PNA type HP 85070-Ds was used to complete the test. The PNA was calibrated in the 100 MHz-40 GHz frequency band. The S-parameters results do not show substantial variation in Figure 15. These findings confirmed that the suggested antenna has a broad BW that meets the requirements of 5G (lower and higher bands), X-band, Ka and Ku, and satellite communication. Furthermore, there is sufficient isolation between each port (S\({}_{21}\) less than \(-18\) dB). Figure 14: The transmission coefficient results of MTM-based MAVA at each stage. Figure 13: The S\({}_{11}\) results of MTM based MAVA for each stage. Figure 16 shows the proposed antenna's simulated SCD after MTM has been implemented, while Ant 1 (port 1) or Ant 2 (port 2) is operational at different bands.