## 3 Reflector Experimental Validation  
The selected CubeSat antenna is designated for utilization in dual polarizations for remote sensing applications. Its satisfactory performance, especially in cross-polarization, is essential in both polarizations. Since the selected feed support is along the \(z\)-axis of the reflector, the vertical polarization of the feed excites strong currents on its surface. These currents radiate a linearly polarized wave with vertical polarization, which manifests as a strong cross-polarization on the reflector axis. For horizontal polarization of the feed, the currents on the feed support will be much lower, and the adverse effects on the cross-polarization would not exist. For this reason, the current study was conducted for vertical polarization of the feed to determine its worst case performance. The test antenna consists of the prototype reflector, as described in Figure 9a, along with the feed array discussed in Section 2.2. The reflector is made of aluminum with a thickness of 2 mm, chosen to meet the rigorous demands of space missions. The reflector main beam direction aligns along the \(z\)-axis. An aluminum metal rod provides support for the feed, which is horizontal in Figure 9a and terminates with an acrylic base. The objective of these measurements is to confirm that the radiation performance of the reflector matches the simulations. It is essential to highlight that the experimental model incorporates the feed support, which was not accounted for in the simulation. This support scatters the feed radiation, which becomes potent as a result of the strong current generated on the supporting rod by the feed polarization. This, in turn, leads to pronounced cross-polarization in the H-plane. Both the reflector and feed were set up in the measurement facility, as depicted in Figure 9b, where the feed polarization is vertical. The antenna underwent testing at the antenna and microwave lab, University of Manitoba, which is equipped for radiation measurements up to 40 GHz. The radiation pattern was assessed in both the elevation and azimuth planes at 17.2 GHz. The measured co- and cross-polarization radiation patterns in both the E- and H-planes at 17.2 GHz are depicted in Figure 10, showing a good match with the simulated patterns, specifically for the co-polarization. There is an evident discrepancy in the cross-polarization data, particularly in the E-plane, which can be attributed to the same factors mentioned in the feed radiation pattern measurement, along with inaccuracies in the assembly of the reflector. The cross-polarization in the E-plane shows as null on the boresigh, a good indication of the symmetric feed alignment. It however has a peak in the  
Figure 8: The normalized E- and H-plane radiation patterns at 17.2 GHz.  
H-plane caused primarily by the scattered field of the feed support, and cross-polarization of the feed itself, as shown in Figure 6b. The measured HPBW in the E- and H-planes are 8.2\({}^{\circ}\) and 9.7\({}^{\circ}\), respectively. In the E-plane, the measured SLL is \(-\)15.2 dB, while in the H-plane, it is \(-\)16 dB. The measured cross-polarization level remains below \(-\)26 dB for both measured and calculated data. The antenna's gain offers a comprehensive evaluation of its performance, encompassing all sources of losses within the system. The measured gain of the reflector is 24.5 dBi, closely matching the simulated value of 25 dBi. The measurement discrepancy of \(-\)0.5 dB is attributed to various factors, such as assembling inaccuracies, potential alignment inaccuracies, calibrating errors, and uncertainties in measurements. Table 3 presents the measured gain, cross-polarization, and SLL for both cuts.