A cutoff waveguide path is provided in a part of a dielectric waveguide comprising
a pair of main conductive layers formed on an upper and a lower surfaces of a dielectric
and groups of conductive vias arranged in the direction of signal transmission
with a space of a distance less than of a signal wavelength between the
conductive vias, and provided in the cutoff waveguide path is a resonator having
dielectric vias formed of a dielectric having a higher dielectric constant than
that of a dielectric forming the dielectric waveguide. With this construction,
a dielectric waveguide type filter easily designed and manufactured can be obtained.
