Continuously Frequency-Tunable Horn Filtennas Based on Dual-Post Resonators

Figure 6

Microwave horn filtenna reflection coefficient. Conf. I (d₁ = 17.70 mm and d₂ = 19.96 mm) centered at 2.56 GHz; Conf. II (d₁ = 19.0 mm and d₂ = 12.3 mm) centered at 3.1 GHz; and Conf. III (d₁ = 13.0 mm and d₂ = 13.5 mm) centered at 3.5 GHz.