Abstract: A polarized waveguide filter is formed in which the polarized waveguide filter includes a first rectangular waveguide; a second rectangular waveguide; and a rectangular cavity resonator that has a first edge surface connected to an electromagnetic wave exit plane of the first rectangular waveguide via a coupling unit, and has a second edge surface facing the first edge surface and connected to an electromagnetic wave incident plane of the second rectangular waveguide via a coupling unit, and excites each of a TE10 mode and a TE20 mode of an electromagnetic wave, and the rectangular cavity resonator has two first wall surfaces and two second wall surfaces narrower in area than the first wall surfaces, and a protrusion that shifts a resonance frequency of the TE10 mode and a resonance frequency of the TE20 mode by respective amounts different from each other is provided on at least one of the two first wall surfaces, in such a way as to protrude outward from the rectangular cavity resonator.

Abstract: A polarized waveguide filter is formed in which the polarized waveguide filter includes a first rectangular waveguide; a second rectangular waveguide; and a rectangular cavity resonator that has a first edge surface connected to an electromagnetic wave exit plane of the first rectangular waveguide via a coupling unit, and has a second edge surface facing the first edge surface and connected to an electromagnetic wave incident plane of the second rectangular waveguide via a coupling unit, and excites each of a TE10 mode and a TE20 mode of an electromagnetic wave, and the rectangular cavity resonator has two first wall surfaces and two second wall surfaces narrower in area than the first wall surfaces, and a protrusion that shifts a resonance frequency of the TE10 mode and a resonance frequency of the TE20 mode by respective amounts different from each other is provided on at least one of the two first wall surfaces, in such a way as to protrude outward from the rectangular cavity resonator.