# Flexible Antennas for a Sub-6 GHz 5G Band:
## 4 Flexible Antennas for a Sub-6 GHz 5G Band
### Flexible MIMO Antennas for Sub-6 GHz 5G Band
#### 4.3.5 Transparent Flexible Antenna
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Ref**} & \multirow{2}{*}{\begin{tabular}{c} **Size** \\ **(mm\({}^{3}\))** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Bandwidth** \\ **(GHz)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Isolation** \\ **(dB)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Number of** \\ **Elements,** \\ **Technique** \\ \end{tabular} } & \multirow{2}{*}{**Gain**} & \multirow{2}{*}{**SAR**} & \multirow{2}{*}{**Bending/Effect**} & \multirow{2}{*}{**ECC**} & \multirow{2}{*}{**DG**} & \multirow{2}{*}{**TARC**} & \multirow{2}{*}{**MEG**} & \multirow{2}{*}{**CCL** \\  & & & & **Isolation** \\  & & & **Technique** & & & & & & & & & \\ \hline \multirow{2}{*}{\([73]\)} & \(\begin{array}{c}59\times\\ 29\times 0.1\end{array}\) & \(\begin{array}{c}2.35-2.55\\ 4.92-5.37\end{array}\) & \multirow{2}{*}{19} & \multirow{2}{*}{2, Defected ground} & \multirow{2}{*}{3.79} & \multirow{2}{*}{\begin{tabular}{c} 0.64 for \\ plane \\ \end{tabular} } & \multirow{2}{*}{**SAR**} & \multirow{2}{*}{**Bending/Effect**} & \multirow{2}{*}{**ECC**} & \multirow{2}{*}{**DG**} & \multirow{2}{*}{**TARC**} & \multirow{2}{*}{**MEG**} & \multirow{2}{*}{**CCL** \\  & & & & & & & & & & & \\ \hline \multirow{2}{*}{\([74]\)} & \(\begin{array}{c}110\times\\ 97\times 1.4\end{array}\) & \(\begin{array}{c}1.5-3.8\\ 4.2-6.2\end{array}\) & \multirow{2}{*}{25–33} & \multirow{2}{*}{4, Meander lines} & \multirow{2}{*}{2.0–5.0} & \multirow{2}{*}{\begin{tabular}{c} 0.62 for \\ surface \\ \end{tabular} } & \multirow{2}{*}{**SAR**} & \multirow{2}{*}{**Bending/Effect**} & \multirow{2}{*}{**ECC**} & \multirow{2}{*}{**DG**} & \multirow{2}{*}{**TARC**} & \multirow{2}{*}{**MEG**} & \multirow{2}{*}{**(**GB**)} & \multirow{2}{*}{**(**GIS/s/Hz**)} & \multirow{2}{*}{**(**GIS/s/Hz**)} \\  & & & & & & & & & & & \\ \hline \multirow{2}{*}{\([75]\)} & \(\begin{array}{c}55\times\\ 35\times 1\end{array}\) & \multirow{2}{*}{3–11} & \multirow{2}{*}{19} & \multirow{2}{*}{2, Stub at the ground} & \multirow{2}{*}{-} & \multirow{2}{*}{\begin{tabular}{c} 0.62 for \\ surface \\ \end{tabular} } & \multirow{2}{*}{-} & \multirow{2}{*}{\
\begin{tabular}{c} 0.66 \(<\)9.975 \\ 1.6 \(\begin{array}{c}\text{\&}\\ \text{\&}\end{array}\) & -} & \multirow{2}{*}{0.06} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{0.2} \\  & & & & & & & & & & \\ \hline \multirow{2}{*}{\([76]\)} & \(\begin{array}{c}110\times\\ 116\times 1\end{array}\) & \multirow{2}{*}{2.22–3.85} & \multirow{2}{*}{30} & \multirow{2}{*}{4, PubMed method from the ground} & \multirow{2}{*}{0.56} & \multirow{2}{*}{-} & \multirow{2}{*}{
\begin{tabular}{c} Horizontal and \\ Vertical Bend- \\ in reflection \\ coefficient \\ \end{tabular} } & \multirow{2}{*}{0.2} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{0.2} \\  & & & & & & & & & & \\ \hline \multirow{2}{*}{\([77]\)} & \(\begin{array}{c}55\times\\ 55\times 0.2\end{array}\) & \(\begin{array}{c}3.34-5.01\\ 8.9-9.2\end{array}\) & \multirow{2}{*}{20} & \multirow{2}{*}{4, Defected ground} & \multirow{2}{*}{4} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} \\  & & & & & & & & & & & \\ \hline \multirow{2}{*}{\([77]\)} & \(\begin{array}{c}55\times\\ 55\times 0.2\end{array}\) & \(\begin{array}{c}3.9-9.2\end{array}\) & \multirow{2}{*}{20} & \multirow{2}{*}{4, Defected ground} & \multirow{2}{*}{4} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} \\  & & & & & & & & & & & \\ \hline \multirow{2}{*}{\([81]\)} & \(\begin{array}{c}50\times\\ 35\times 1\end{array}\) & \(\begin{array}{c}4.65-4.97\\ 4.67-4.94\end{array}\) & \multirow{2}{*}{17.47} & \multirow{2}{*}{2, the distance between the elements} & \multirow{2}{*}{1.65} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{0.02} & \multirow{2}{*}{9.96} & \multirow{2}{*}{\(>\)\(-\)\(\frac{15}{2}\)} & \multirow{2}{*}{1} & \multirow{2}{*}{0.10} \\  & & & & & & & & & & & \\ \hline \multirow{2}{*}{\([82]\)} & \(\begin{array}{c}66\times\\ 45\times\\ 0.625\end{array}\) & \multirow{2}{*}{2.21–6} & \multirow{2}{*}{15} & \multirow{2}{*}{4, Defected ground} & \multirow{2}{*}{0.53} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} \\  & & & & & & & & & & & \\ \hline \hline \end{tabular}
\end{table}