## 3 Result Analysis and Discussion
CCL specifies the maximum possible data transfer rate that suffers significant degradation. To prove lossless data transmission, a well implemented MIMO system should achieve a rate of \(0.5\,\mathrm{bits/s/Hz}\). Simply said, CCL alerts the user to the point at which further communication cannot be conducted without risk. CCL may be computed using either Equation (10) or Equation (11), respectively. \[\mathrm{CCL}=-\mathrm{log}_{2}\mathrm{Det}\Big{(}\mathcal{O}^{R}\Big{)} \tag{10}\]  
\[\mathcal{O}^{R}=\left[ \begin{array}{cc}\mathcal{O}_{11}&\mathcal{O}_{12}\\ \mathcal{O}_{21}&\mathcal{O}_{22}\end{array} \right] \tag{11}\]  
Here, the main goal behind these four phases is to achieve a higher gain, which was achieved using the proposed MIMO structures. The simulated and measured channel capacity loss response for all of the proposed design structures is represented in Figure 14. The CCL response, both simulated and measured, is lower than 0.1 for all of the proposed design structures and within an acceptable range. The TARC values for the proposed four MIMO antennas are shown in Figure 15. For all of the configurations, the TARC value is less than 0 dB. DS-1 represents \(-19.92\) dB at 10.9 GHz. DS-2 represents a TARC value of \(-19.52\) dB near 4.55 GHz. In DS-3, a TARC value of \(-50\) dB is achieved near 3.10 GHz. DS-4 shows a TARC value of \(-54.55\) dB at 5.25 GHz. The peak of TARC was observed near the resonating frequency. The comparison of the presented MIMO structure with the other structures is shown in Table 4[31; 32; 33; 34; 35; 36; 37]. A comparison of the design is made for five main aspects of the MIMO design. The first aspect is its isolation which needs to be high, and here, in our design, it is 35 dB. The dimension of the proposed antenna is miniaturized in nature and the substrate used is low-cost, which makes it a good pick for MIMO antenna design. The DG of the proposed antenna is also almost 10 dB. The peak gain of the design is around 20.44 dB, which is higher than that of the other designs. The number of ports is two for the proposed research. It is concluded that the presented work provides a remarkably good peak gain, as well as good isolation and DG. Where, NR represents not reported. Figure 13: The simulated and measured MEG response of the proposed DS-1, DS-2, DS-3, and DS-4. Figure 14: The simulated and measured CCL response of the proposed DS-1, DS-2, DS-3, and DS-4. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Reference** & **Dimension (mm\({}^{2}\))** & **Ports** & \
\begin{tabular}{c} **Isolation** \\ **(dB)** \\ \end{tabular} & **DG (dB)** &
\begin{tabular}{c} **Gain** \\ **(dB)** \\ \end{tabular} \\ \hline Proposed design & \(35\times 50\) & 2 & 35 & 10 & 20.44 \\ [31] & \(30\times 15\) & 2 & 35.8 & \textgreater{}9.99 & 5.42 \\ [32] & \(48\times 31\) & 4 & 21 & NR & 14 \\ [33] & \(20\times 20\) & 2 & 24 & 9.9 & 8 \\ [34] & \(19\times 19\) & 4 & 35 & NR & 14 \\ [35] & \(31\times 31\) & 8 & 16.1 & NR & 6.4 \\ [36] & \(35\times 30\) & 4 & 17 & \textgreater{}9.96 & 8.3 \\ [37] & \(12\times 51\) & 4 & 25 & NR & 10.6 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Various MIMO antennas are compared to the presented design. Figure 15: TARC of proposed four MIMO structures. (**a**) TARC of DS-1. (**b**) TARC of DS-2. (**c**) TARC of DS-3. (**d**) TARC of DS-4.