| 摘要 |
PURPOSE:To obtain a small-sized band-stop filter which has large attenuation in a stop band and small insertion loss in a normal band by projecting outward the part of an H surface close to a dielectric resonator. CONSTITUTION:The part 11H of the H surface of a waveguide 11 close to the dielectric resonator 12 is projected out of the waveguide by length b' at the upper side and by length b'' at the lower side. Consequently, the inductance L by the operation of magnetic energy at the projection part is formed and inserted in series of the parallel resonance circuit consisting of capacity CD and inductance LD corresponding to the dielectric resonator 12. Further, an E wave having an electric field in the propagation component of the wave is generated on surfaces 11A-11D as discontinuance points of the projection part and this E wave is a damped wave, so electrostatic capacity C is formed and inserted in parallel. Consequently, matching is attained in a passing band and the interval between the dielectric resonator 12 and H surface become larger to increase nonloaded Q, so the expected purpose is attained. |
