Evanescent Mode Cylindrical Cavity Filter
Application ID: 12015
An evanescent-mode cavity filter is resonant at a frequency lower than its original fundamental mode frequency. Evanescent mode resonance can be realized by creating a discontinuity or reactance inside the cavity.
The basic model was modified by the addition of a metal box at either end representing a housing. Inside a dielectric substrate and a microstrip line coupled into the cavity.
The electric field distribution shows that the dielectric tube inside the cavity does not distort the distribution significantly.