# A Low-Profile Dual-Polarized Transmitarray with Enhanced Gain and Beam Steering at Ku Band
## 6 Comparison with Other Works  
The performance of this proposed TA is compared with some related work listed in Table 4. It is observed that the proposed TA has a lower profile, having thickness \(\rho\) = 0.126\(\lambda\)0 [49; 50; 51; 52]. It consists of three layers with a reduced array size of A = 57.9\(\lambda_{0}\)\({}^{2}\)[49; 51; 53]. This proposed TA does not require an air gap in between the substrates, offering improved robustness, compactness, and ease of fabrication. Moreover, the low F/D = 0.6 makes this TA more compact than [51; 52]. Moreover, the 8-phase state having less than \(\alpha_{\rm T}\) = 1.3 dB transmission loss with dual linear polarized components transmission capability is not achieved in [49; 50; 53]. For the case of beam steering, the proposed TA can scan \(\gamma_{\rm max}\) = \(\pm\)30\({}^{\circ}\), which is greater than [49; 53]. This work achieves the lowest scan loss among the reference works of \(\triangle\)GMSLI = 2.73 dB at f\({}_{1}\) = 12.4 GHz [49; 50; 51; 53]. However, the aperture efficiency \(\eta\) is not better in comparison with the reference papers reported in Table 4 except [53]. It can be concluded that the lower profile is achieved at the cost of aperture efficiency \(\eta\) or gain G.  
Therefore, by considering all the factors, the proposed transmitarray can be considered (i) novel (metal patterns with circular geometry), (ii) low profile (to parity of performance),  
\begin{table}
\begin{tabular}{l l l l l l l l} \hline \hline
**Ref.** & **[PERSON] et al.**, & **[PERSON] et al.**, & **[PERSON]** & **[PERSON] et al.**, & **[PERSON] et al.**, & **[PERSON] et al.**, & **This Work** \\  & **2017 [49]** & **2020 [50]** & **et al.**, 2016 [51] & **[52]** & **2021 [53]** & **This Work** \\ \hline Frequency f (GHz) & 27.5 & 10 & 12 & 15 & 12.5 & 12 & 12.4 \\ No. of layers & 2 & 3 & 5 & 3 & 3 & 3 \\ Thickness \(\rho\) (\(\lambda_{0}\)) & 0.18 & 0.133 & 0.582 & 0.165 & 0.083 & 0.126 & 0.13 \\ Array size A (\(\lambda_{0}\)\({}^{2}\)) & 86.06 & 16.0 & 64.0 & 38.48 & 90.9 & 57.9 & 62.35 \\ Gain G (dB) & 24.2 & 19.3 & 23.0 & 23.06 & 22.7 & 21.0 & 19.97 \\ Scan range \(\gamma_{\rm max}\) & \(\pm\)27 & +60 & \(\pm\)35 & \(\pm\)30 & \(\pm\)21 & \(\pm\)30 & \(\pm\)30 \\ (degree) & \(\triangle\)G (dB) & 3.7 & 4.15 & 3.0 & 3.6 & 2.7 & 4.03 & 2.73 \\ F/D & 0.50 & 0.60 & 0.78 & 0.75 & 0.59 & 0.60 & 0.60 \\ Polarization & Dual & Single CP & Ins. * & Dual LP and & Single LP & Dual & Dual \\ Side Lobe Level & \(-\)18.4 & \(-\)17.7 & \(-\)15.0 & \(-\)35.0 & \(-\)15.0 & \(-\)20.8 & \(-\)18.5 \\ SLL (dB) & 240\({}^{\circ}\) & 180\({}^{\circ}\) & 360\({}^{\circ}\) & 360\({}^{\circ}\) & 360\({}^{\circ}\) & 360\({}^{\circ}\) & 360\({}^{\circ}\) \\ Air gap & Yes & No & No & Yes & No & No & No \\ Aperture & 24.5 & 40.2 & 34.64 & 42.3 & 15.2 & 17.0 & 13.0 \\ Efficiency \(\eta\) (\%) & & & & & & & \\ \hline \hline \end{tabular} \({}^{*}\)Ins. = Insensitive.  
\end{table}
Table 4: Comparison of proposed TA with other works.  
(iii) dual-polarized, (iv) simple to be fabricated, (v) with good scan loss at 12.4 GHz and (vi) with good steering angle.