Hybrid Perturbations in Stacked Patch-Ring Circularly Polarized Microstrip Antennas for CubeSat Applications Figure 12. (a) AR versus frequency plots varying the positive perturbation. (b) AR versus frequency plots varying the negative perturbation. Figure 10. (a) Proposed hybrid antenna on a 2U CubeSat. (b) Simulation model for the antenna with a 2U CubeSat. Photographs of the driven patch and the parasitic ring are shown in Figure 13. The antenna scattering parameters were measured in a Wiltron 37369A 40 MHz-40 GHz Vector Network Analyzer. The measured S11 < -10 dB Figure 11. AR comparison. (a) Changing the size of the CubeSat. (b) Changing the substrate dimension on a 2U CubeSat. 30 Figure 13. (a) Driven patch of the fabricated antenna. (c) Top view of the fabricated antenna. (c) Fabricated antenna under test. IEEE A&E SYSTEMS MAGAZINE MARCH 2022