Patent ID: 6608533
Filing Date: 2003-08-19
Classification: H01P

Abstract:
A duplexer of an integrated shape comprising a receiving terminal for connection to a receiving circuit, a transmitting terminal for connection to a transmitting circuit, an antenna terminal for connection to an antenna, a first transmission line, a second transmission line, a third transmission line, a transmission line for a transmitting filter, a plurality of capacitor elements for said transmitting filter, a plurality of capacitor elements for a receiving filter, a plurality of resonators for said transmitting filter and a plurality of resonators for said receiving filter,wherein (1) one end of said first transmission line is connected to one end of said second transmission line and one end of said third transmission line, (2) said transmission line for said transmitting filter is connected to said plural resonators for said transmitting filter via said capacitor elements for said transmitting filter, respectively, (3) the other end of said third transmission line is connected to one end of said transmission line for said transmitting filter, (4) the other end of said transmission line for said transmitting filter is connected to said transmitting terminal, (5) said resonators for said receiving filter arranged in parallel are connected to one another via said capacitor elements for said receiving filter, (6) a said resonator disposed at one end of the arrangement of said plural resonators for said receiving filter is connected to the other end of said first transmission line via a said capacitor element for said receiving filter, (7) a said resonator disposed at the other end of the arrangement of said plural resonators is connected to said receiving terminal via a said capacitor element for said receiving filter, and (8) the other end of said second transmission line is connected to said antenna terminal, and wherein (1) said duplexer includes a plurality of dielectric layers laminated together, (2) at least one of said transmission lines is located between two of said dielectric layers of said plurality of dielectric layers, (3) at least one of said capacitor elements is located between two of said dielectric layers of said plurality of dielectric, layers, and (4) at least one of said resonators is located between two of said dielectric layers of said plurality of dielectric layers.