Abstract
Two concentric dual-coaxial SIR filters with different structures are proposed. The first is that the upper resonant cap wraps the lower resonant cap; the second is that the cap of the upper resonator no longer wraps the lower resonator. The dual-coaxial quarter-wavelength SIR structure improves the anti-vibration capability of the resonator, and the structure makes full use of the resonator space and improves the unloaded Q value. The insertion loss of the first filter is less than 0.3 dB, and the insertion loss of the second filter is less than 1.5 dB.
Disclosure statement
No potential conflict of interest was reported by the author(s).