E-surface film waveguide filter

The invention discloses an E-surface film waveguide filter. The E-surface film waveguide filter comprises a rectangular waveguide and a metal film which is arranged in a rectangular waveguide cavity and is parallel to the E surface of the rectangular waveguide, a group of windows which are arranged along the waveguide propagation direction are formed in the metal film, and each window forms a resonant cavity; the edge of at least one window is provided with a tooth-shaped protruding structure pointing to the middle of the window, and the tooth-shaped protruding structure is used for forming capacitance loading. Capacitance loading of the resonant cavity of the filter is achieved by ingeniously arranging the tooth-shaped protruding structure on the edge of the window of the metal film, thelarger the loading is, the smaller the size of the filter is, and therefore the size of the filter is effectively reduced. By adopting the technical scheme of the invention, the filters with the sameorder can be made smaller,