## 4 Proposed Deployment of the Reflector  
Accommodating a large-scale reflector antenna within 1U is challenging and involves intricate coordination between RF and mechanical design. Parabolic reflector deployment, as in [26], necessitates a significant number of ribs to uphold a reasonable deviation from an ideal surface. The gain loss of such reflectors is predominantly influenced by the  
Figure 10: Measured and calculated radiation patterns of the cylindrical reflector at 17.2 GHz: (a) E-plane and (b) H-plane.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Plane**} & \multicolumn{2}{c}{**Gain (dBi)**} & \multicolumn{2}{c}{**Xpol (dB)**} & \multicolumn{2}{c}{**SLL (dB)**} & \multicolumn{2}{c}{**HPBW**} \\  & **Sim.** & **Meas.** & **Sim.** & **Meas.** & **Sim.** & **Meas.** & **Sim.** & **Meas.** \\ \hline E & 25 & 24.5 & \(-\)31.5 & \(-\)26.6 & \(-\)16 & \(-\)15.4 & 8\({}^{\circ}\) & 8.2\({}^{\circ}\) \\ H & 25 & 24.47 & \(-\)32.2 & \(-\)28.1 & \(-\)14 & \(-\)16 & 9.6\({}^{\circ}\) & 9.7\({}^{\circ}\) \\ \hline \hline \end{tabular}
\end{table}
Table 3: Measurement data.  
Figure 9: (a) The antenna system prototype includes the cylindrical reflector and the array feed and (b) the reflector system in the antenna test facility.  
number of ribs. Additionally, positioning such a large number of ribs near the reflector can present a complex task and increases the risk of rib jamming during deployment. Thanks to the cylindrical shape and the compact dimensions of the proposed design, achieving the deployable mechanism entails less complexity in contrast to other intricate approaches [26, 27]. The proposed deployable mechanism is depicted in Figure 11. This mechanism allows the antenna to be stowed within 1U. To accomplish deployment, the top wall and one of the side walls need to be removed. The sequence from full stowage to full deployment is depicted in Figure 11 through Figure 11. The fully stowed antenna is illustrated in Figure 11, with both the feed and reflector contained within a 1U space. The reflector is segmented into two equal parts linked to the CubeSat wall via hinges. To allow the sections to slide over each other, the left part of the reflector is nudged forward, reducing the reflector width to 87 mm to prevent any contact with the 1U walls and rails (standard CubeSat rails measure 6 \(\times\) 6 mm\({}^{2}\)). The beginning of the full deployment process involves rotating the reflector upward out of the 1U at a 112\({}^{\circ}\) angle, as shown in Figure 11. The correct positioning of the feed to illuminate the reflector is ensured by a support connected to the 1U base. When stowed, it rotates 47\({}^{\circ}\) towards the reflector, allowing ample space for the reflector to be stored within the 1U, as demonstrated in Figure 11. In Figure 11, the two parts of the reflector slide over each other, and then, the left part is pushed back to its original position, reestablishing the reflector's full width of 110 mm. The final step involves rotating the feed by 47\({}^{\circ}\) away from the reflector to facilitate full deployment, as depicted in Figure 11. There is available space at the bottom, near each side of the 1U unit, which can be used to house the power source without interfering with the deployment mechanism or compromising the reflector's performance.