| 摘要 |
A dielectric filter comprises an input terminal (1), an output terminal (2), and a voltage control terminal (3), a plurality of dielectric resonators (5, 6, 7) electrically connected between said input terminal (1) and said output terminal (2), a first adjustable capacitance element (D1) electrically connected to at least one of said plurality of dielectric resonators (5, 6, 7) and to said voltage control terminal (3), the first adjustable capacitance element (D1) being adjustable by a control signal from said voltage control terminal (3), and the first adjustable capacitance element (D1) being on a first path interconnecting at least two of said plurality of dielectric resonators (5, 6, 7) of a bandpass filter, a second adjustable capacitance element (D2) electrically connected to at least one of said plurality of dielectric resonators (5, 6, 7) and to said voltage control terminal (3), the second adjustable capacitance element (D2) being adjustable by a control signal from said voltage control terminal (3), and the second adjustable capacitance element (D2) being on a second path interconnecting at least two of said plurality of dielectric resonators (5, 6, 7) of said bandpass filter, wherein the first path and the second path provide respective attenuation poles of said bandpass filter. <IMAGE> |
