## 5 Results
The maximum gain during azimuth steering at 30\({}^{\circ}\) was 16.13 dB without the FSS and 16.68 dB with the FSS, while during elevation steering at 30\({}^{\circ}\), it was 15.74 dB without the FSS and 15.90 dB with the FSS. Table 3 shows that this paper demonstrates superior research results, as it maintains beam steering characteristics while having the lowest insertion loss compared to other studies. Although the designed FSS demonstrated effective harmonic suppression and wide-angle beam steering in radar systems, this study has several limitations and suggests directions for future research. Firstly, the current study focused on a single frequency band (3.0 GHz for operation and 6.0 GHz for harmonics). Future research could explore optimizing FSS \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Ref**} & \multirow{2}{*}{**FSS Filter Type**} & \multicolumn{2}{c}{**Unit Cell Size**} & \multirow{2}{*}{**Height**} & \multirow{2}{*}{**Insertion**} & \multirow{2}{*}{**Harmonic**} & \multirow{2}{*}{**Bear Tilting**} \\  & & **(Length \(\times\) Width) [\(\lambda\)]** & & & & \\ \hline
[11] & Dual Band-Pass Filter & 0.113 \(\times\) 0.113 & 1 mm & 0.5 & N/A & [PERSON], [PERSON] (60\({}^{\circ}\)) \\ \hline
[12] & Band-Stop Filter & 0.15 & 0.16 mm & 0.5 & o & N/A \\ \hline
[13] & Dual Band-Pass Filter & 0.1 & 23 nm & 0.98 & o & [PERSON], [PERSON] (30\({}^{\circ}\)) \\ \hline
[14] & Dual Band-Pass Filter & 0.2 & 5.5 mm & 0.3 & o & [PERSON], [PERSON] (60\({}^{\circ}\)) \\ \hline Proposed Work & Band-Pass, Band-Stop Filter & 0.105 & 0.25 mm & 0.12 & o & [PERSON], [PERSON] (30\({}^{\circ}\)) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Comparison of various FSS. structures for multi-band applications, broadening the technology's applicability in more diverse communication systems. Additionally, the FSS was tested under controlled conditions, and further studies should evaluate its performance in more complex environments, such as urban or highly reflective settings, to ensure robustness and reliability in practical applications. Moreover, while this study has demonstrated the effectiveness of FSS in radar systems, future research could investigate using FSS to reduce interference between base stations in cellular networks, decrease the Radar Cross Section (RCS) of stealth aircraft, or enhance indoor communication quality in commercial office buildings. By addressing these limitations and exploring these future research directions, the potential applications and performance of FSS can be significantly enhanced, paving the way for more efficient and versatile electromagnetic wave control solutions in various fields. Conceptualization, D.H.H. and K.C.H. ; methodology, D.H.H. ; software, D.H.H. ; validation, D.H.H. ; formal analysis, D.H.H. and K.C.H. ; investigation, D.H.H. and T.J.; measurement D.H.H., J.H.K., and T.J.; resources, D.H.H. ; data curation, D.H.H. ; draft preparation, D.H.H. ; writing--review and editing, D.H.H. and K.C.H. ; supervision, K.C.H. ; project administration, K.C.H. ; funding acquisition, K.C.H. All authors have read and agreed to the published version of the manuscript. This research was supported by the Challengeable Future Defense Technology Research and Development Program through the Agency for Defense Development (ADD) funded by the Defense Acquisition Program Administration (DAPA) in 2023 (No.912902601). Not applicable. The data presented in this study are available in the article. The authors declare no conflicts of interest.