## 7 Conclusions  
The MS reflector displayed an almost \(100\%\)\(f_{\text{res}}\) tuning performance that covered all of the X-band and half of the Ku-band with a substantial dynamic phase reflection rangeability. The unit cell losses were higher than expected in the preliminary simulation, mainly because the \(R_{S}+R_{P}\) values were higher in the prototype with measured values higher than \(10\)\(\Omega\). This parameter can be improved by the experience gained in this work with a more accurate manufacturing process. The MS reflector allowed for significant steering ability at \(12\) GHz and above, as shown in Figure 15 and Tables 2 and 3. These abilities allow for improving satellite communications (QoS) in the X-band and Ku-band.  
The design optimization for working frequencies of the MS reflector gave high weight to maximizing the dynamic phase range. In practice, the higher-than-acceptable losses were the main barrier. The simulations showed broad agreement with the measurements for all operating frequencies and capacitance values, indicating that the assumptions regarding the model and the definitions of the simulations were reasonable and valid. The ability to realize an MS reflector at a higher operating frequency based on the tunable mushroom structure is limited. The unit cell \(C_{int}\) value reduction, which requires reducing the unit cell sizes, is limited due to the diode located at the front, with its non-negligible size relative to the unit cell area size [17; 18; 19]. Reducing the patch size beyond what is done in this work is ineffective regarding reducing the \(C_{int}\)[11; 36]. Reducing the \(L_{int}\) value by reducing the dielectric substrate thickness of the unit cell allows for a significant increase in the operating frequency but, on the other hand, increases the \(Q\) and losses and reduces the bandwidth. A substantial increase in the operating frequency for realizing this MS reflector concept without compromising performance and even with improved performance is possible using other geometries [18; 19].  
Conceptualization, D.R.; methodology, D.R.; software, D.R.; validation, D.R.; data curation, D.R.; formal analysis, D.R.; investigation, D.R.; resources, D.R. and A.A.; writing--D.R.; writing--review and editing, D.R. and A.A.; visualization, D.R.; supervision, A.A.; project administration, D.R.; funding acquisition, A.A. Both authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
The authors declare no conflict of interest.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \(\theta\) **Calc/Sim (\({}^{\circ}\))** & **SLL (dB)** & **RCS peak (dB)** & **Efficiency** \\ \hline \(0^{\circ}/0^{\circ}\) & \(13.3\) & \(0\) & \(1\) \\ \(0^{\circ}/0^{\circ}\) & \(13.3\) & \(-1.1\) & \(0.776\) \\ \(10^{\circ}/10^{\circ}\) & \(7.23\) & \(-3.97\) & \(0.4\) \\ \(30^{\circ}/31.25^{\circ}\) & \(6.76\) & \(-5.6\) & \(0.276\) \\ \(50^{\circ}/49.32^{\circ}\) & \(4.7\) & \(-6.58\) & \(0.22\) \\ \hline \hline \end{tabular}
\end{table}
Table 2: Parameters for steering angles \(\theta\) at \(12\) GHz.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \(\theta\) **Calc/Sim (\({}^{\circ}\))** & **SLL (dB)** & **RCS peak (dB)** & **Efficiency** \\ \hline \(0^{\circ}/0^{\circ}\) & \(13.3\) & \(0\) & \(1\) \\ \(0^{\circ}/0^{\circ}\) & \(13.3\) & \(-0.83\) & \(0.826\) \\ \(10^{\circ}/10.27^{\circ}\) & \(10.36\) & \(-1.89\) & \(0.647\) \\ \(30^{\circ}/29.13^{\circ}\) & \(6.72\) & \(-2.92\) & \(0.51.1\) \\ \(50^{\circ}/51.38^{\circ}\) & \(5.93\) & \(-6.83\) & \(0.275\) \\ \hline \hline \end{tabular}
\end{table}
Table 3: Parameters for steering angles \(\theta\) at \(13.5\) GHz.