Patent ID: 6833773
Filing Date: 2004-12-21
Classification: H01P

Abstract:
A dielectric duplexer comprising:a pair of dielectric filters, each dielectric filter comprising: a plurality of resonance lines substantially parallel to each other arranged substantially entirely on a substantially planar upper surface of a dielectric substrate; and an outer conductor formed on the lower surface of the dielectric substrate; wherein each of the plurality of resonance lines has parts near or at both ends thereof which are open-circuited, and the width of at least one of the resonance lines is changed in at least one position along the longitudinal direction of the resonance line to form a stepped part; said pair of dielectric filters both being formed on a single dielectric plate to be used as a transmitting side filter and a receiving side filter, respectively; a transmitted-signal input terminal coupled to a first-stage resonance line of the transmitting side filter; a received-signal output terminal coupled to a last-stage resonance line of the receiving side filter; and an antenna terminal coupled to a last-stage resonance line of the transmitting side filter and a first-stage resonance line of the receiving side filter, respectively.