## 7 Antenna Qualification and Acceptance Test
### Verification of Results After Qualification Tests  
Once the environmental and mechanical qualification tests for the space antenna are completed, and the measurements taken between each test have validated the antenna's functionality final RF measurements are conducted (Figures 22-26). For these measurements, the antenna is removed from the mass dummy and reinstalled on the RF dummy, where not only the S-parameters but also the gain and radiation pattern are measured (final RF functional test). During the qualification tests, the antenna was found to exceed its designated parameters. Specifically, during the TVAC tests, the antenna was subjected to temperatures that \begin{table}
\begin{tabular}{c c} \hline \hline \multirow{2}{*}{**FreqHz**} & **Maximum Predicted Environment Induced by Launch Vehicle** \\  & **and Co-Payload (s) SRS (g)** \\ \hline
100 & 30 \\ \hline
10,000 & 1000 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Temperatures range in TVAC cycles. \begin{table}
\begin{tabular}{c c} \hline \hline
**Environment** & **Shroud Temperature** \\ \hline Hot (Tmax) & +85 \({}^{\circ}\)C [0, +8 \({}^{\circ}\)C] \\ \hline Cold (Tmin) & \(-\)40 \({}^{\circ}\)C [\(-\)8 \({}^{\circ}\)C, 0] \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Profile of g-acceleration values in shock tests. exceeded the required ranges (Table 4) for eight complete cycles without any discernible modification to its physical characteristics or S-parameters. To verify this, a combination of visual inspections and S-parameter measurements was employed. These measurements were conducted before, during, and after each cycle while the antenna was inside the chamber. A subsequent filtration process was deemed necessary in order to remove any reflections that had been introduced by the chamber into the aforementioned graphs. Furthermore, the antenna underwent both vibration and shock tests in accordance with the envelope values defined by the Falcon 9 launcher from SpaceX, with the results of these tests even exceeding the standard qualification requirements. It was only subsequent to the shock tests that a slight variation in the S-parameter response was observed when compared with the reference measurements (Figure 22a). No significant changes were observed in the gain and AR measurements (see Figures 23-26). As a demonstration that the antenna maintains a bandwidth greater than 8% in both impedance matching and axial ratio (AR), Figure 26 is presented. The green dotted lines represent the margins in which AR must meet the requirement of <4 dB. This figure shows the AR as a function of frequency (in boresight) for the antenna mounted on the RF dummy, with measurements taken in an anechoic chamber before and after the qualification process. Although the pre-test measurements were taken only at the up-link and down-link frequencies, a comparison is represented, and the figure clearly shows how the pre- and post-test curves are very close to each other. Therefore, it is demonstrated that the AR  
Figure 24: AR measurement S—band antenna before and after qualification tests campaign. f = 2.03 GHz (the green dotted lines represent the margins in which AR must meet the requirement of <4 dB): (**a**) Port 1; (**b**) Port 2. Figure 25: AR measurement S—band antenna before and after qualification tests campaign, f = 2.205 GHz (the green dotted lines represent the margins in which AR must meet the requirement of <4 dB): (**a**) Port 1; (**b**) Port 2.  
bandwidth, as well as the impedance matching bandwidth of the antenna, is 8%, as required by the ANSER program specification, even after being qualified for space. It is, therefore, concluded that the antenna is qualified for space, with its physical and functional characteristics remaining intact. This is evidenced by the maintenance of its gain pattern characteristics and axial ratio after undergoing all qualification tests (see Figures 22-26).