Abstract: Filter circuitry is provided with a series element and a parallel element. The filter circuitry transmits signals that fall within a certain passband and attenuates signals that don't fall within the certain passband. The series element is comprised of a resonance element having antiresonance characteristics, and the parallel element is comprised of a series circuit including an inductor and a capacitor.

Abstract: The waveguide group branching filter according to the present invention is formed by boring out of two metal blocks constituent circuits including a circular-to-square waveguide multistage transformer 1, the branch waveguide polarizer/branching filter 4, a rectangular waveguide multistage transform 9, the rectangular waveguide H-plane T-branch circuit 10, and waveguide band-pass filters 8, 14 and 18; radio waves V1 and H1, which have their polarization planes vertical and horizontal, respectively, to the branching plane of the branch waveguide polarizer/branching filter 4 in a certain frequency band f1, and a radio wave V2 of the same polarization plane as that of the radio wave V1 in a frequency band f2 higher than the frequency band f1 are incident to an input port P1, and the radio wave V1 is emitted from an output port P2, the radio wave H1 from an output port P3 and the radio wave V2 from an output port P4.

Abstract: Filter circuitry is provided with a series element and a parallel element. The filter circuitry transmits signals that fall within a certain passband and attenuates signals that don't fall within the certain passband. The series element is comprised of a resonance element having antiresonance characteristics, and the parallel element is comprised of a series circuit including an inductor and a capacitor.

Abstract: On each surface of a dielectric substrate, arranged are a first conductor line pattern having a plurality of first line segments and a second conductor line pattern having a plurality of second line segments. Ends of each first conductor line segment overlap the second conductor line segments, and the first and second line segments are connected via through-holes, thereby forming a single spiral conductor line. Each second conductor line segment for connecting adjacent first conductor line segments has a pair of end parts connected to the first conductor line segments via through-holes and a halfway part having a smaller width.

Abstract: On each surface of a dielectric substrate, arranged are a first conductor line pattern having a plurality of first line segments and a second conductor line pattern having a plurality of second line segments. Ends of each first conductor line segment overlap the second conductor line segments, and the first and second line segments are connected via through-holes, thereby forming a single spiral conductor line. Each second conductor line segment for connecting adjacent first conductor line segments has a pair of end parts connected to the first conductor line segments via through-holes and a halfway part having a smaller width.

Abstract: The waveguide group branching filter according to the present invention is formed by boring out of two metal blocks constituent circuits including a circular-to-square waveguide multistage transformer 1, the branch waveguide polarizer/branching filter 4, a rectangular waveguide multistage transform 9, the rectangular waveguide H-plane T-branch circuit 10, and waveguide band-pass filters 8, 14 and 18; radio waves V1 and H1, which have their polarization planes vertical and horizontal, respectively, to the branching plane of the branch waveguide polarizer/branching filter 4 in a certain frequency band f1, and a radio wave V2 of the same polarization plane as that of the radio wave V1 in a frequency band f2 higher than the frequency band f1 are incident to an input port P1, and the radio wave V1 is emitted from an output port P2, the radio wave H1 from an output port P3 and the radio wave V2 from an output port P4.