Abstract: A resonator, a filter, and a communication apparatus that can be easily miniaturized even if the resonant frequency is relatively low are provided. Conductor layers are laminated in the state in which they are partially insulated from each other by a dielectric layer. Conductor openings free from any conductor layer in the laminate direction serve as inductive areas, and the portion where the conductor layers oppose each other with the dielectric layer therebetween serves as a capacitive area CA. With this configuration, the resulting resonator serves as a stepped-impedance-structured slot resonator. By increasing the impedance step ratio of the capacitive area to the inductive areas according to this structure, the resonator is miniaturized. Additionally, the conductor loss of the resonator is reduced by suppressing the intrusion of magnetic field energy to the capacitive area. It is thus possible to obtain a small resonator having high Qo.

Abstract: A resonator, a filter, and a communication apparatus that can be easily miniaturized even if the resonant frequency is relatively low are provided. Conductor layers are laminated in the state in which they are partially insulated from each other by a dielectric layer. Conductor openings free from any conductor layer in the laminate direction serve as inductive areas, and the portion where the conductor layers oppose each other with the dielectric layer therebetween serves as a capacitive area CA. With this configuration, the resulting resonator serves as a stepped-impedance-structured slot resonator. By increasing the impedance step ratio of the capacitive area to the inductive areas according to this structure, the resonator is miniaturized. Additionally, the conductor loss of the resonator is reduced by suppressing the intrusion of magnetic field energy to the capacitive area. It is thus possible to obtain a small resonator having high Qo.

Abstract: A conductive film is provided on a dielectric substrate. The conductive film has conductor opening portions, which serve as inductive regions, and a conductor opening portion, which serves as a capacitive region. Multi-step ring resonator elements, each including a conductor line aggregate, are provided on respective substrates to configure resonator elements. The resonator elements are mounted above the conductor opening portions that serve as the inductive regions. This arrangement provides a resonator having a high Qo.

Abstract: A resonator device including a plurality of resonance units formed on a dielectric substrate, each resonance unit having a plurality of conductor lines forming a capacitive area and an inductive area in a ring shape.

Abstract: A conductive film is provided on a dielectric substrate. The conductive film has conductor opening portions, which serve as inductive regions, and a conductor opening portion, which serves as a capacitive region. Multi-step ring resonator elements, each including a conductor line aggregate, are provided on respective substrates to configure resonator elements. The resonator elements are mounted above the conductor opening portions that serve as the inductive regions. This arrangement provides a resonator having a high Qo.

Abstract: A conductive film is provided on a dielectric substrate. The conductive film has conductor opening portions, which serve as inductive regions, and a conductor opening portion, which serves as a capacitive region. Multi-step ring resonator elements, each including a conductor line aggregate, are provided on respective substrates to configure resonator elements. The resonator elements are mounted above the conductor opening portions that serve as the inductive regions. This arrangement provides a resonator having a high Qo.

Abstract: Ring-shaped resonant elements include respectively conductor lines 2a, 2b, and 2c each formed on a substrate 1 along a full one turn of circumferential length of a ring. Each of the conductor lines 2a, 2b, and 2c has two end portions which additionally extend and which are located such that they closely adjoin each other in a width direction. The respective ring-shaped resonant elements are disposed in a concentric fashion. Capacitive parts are formed in areas in which two ends of respective conductor lines are located in close proximity to each other, and the other parts of the respective conductor lines function as inductive parts. Each conductor line operates as a half-wave transmission line whose both ends are electrically open. It is not needed to form a ground electrode on a surface of the substrate opposite to the surface on which the conductor lines are formed. Thus, a resonator can be formed using a very small number of constituent elements.

Abstract: A transmission line, a resonator, a filter, a duplexer, and a communication apparatus efficiently minimize power losses due to edge effects, thereby having superior loss-reduction characteristics. A continuous line and a plurality of thin lines each having a predetermined length and branching from both sides of the continuous line are formed on a dielectric substrate. With this structure, edges of the individual thin lines substantially do not exist, so that losses due to edge effects can be efficiently minimized.

Abstract: A high-frequency circuit device serving as a resonator includes a substrate and an electrode film which is formed on the surface of the substrate and which includes a conductive film and a dielectric film. The conductive film is formed around the substrate such that both ends of the conductive film overlap each other when viewed in a predetermined cross-section of the substrate, and the dielectric film is inserted between both ends of the conductive film. Accordingly, a self-capacitance portion is formed at the overlapped portion of the conductive film, electric-field energy is accumulated therein, and magnetic-field energy is accumulated inside the substrate. With this step impedance structure, the entire high-frequency circuit device can be miniaturized.

Abstract: A coaxial resonator according to an embodiment of the invention includes a tubular dielectric block, an inner conductor having a thin-film, multi-layer electrode structure, which is formed on an outer surface of a cylindrical shaft received in the hole of the tubular dielectric block, and an outer conductor formed on an outer surface of the tubular dielectric block. The cylindrical shaft is inserted into the hole in the dielectric block, and is held by a holding member and an outer frame.

Abstract: In a resonator having a dielectric member and an electrode formed on the dielectric member, a displacement area (D area) having a high vertical electric field component, and a short or steady area (S area) having a vertical electric field component of zero or close to zero are provided in an interface between the dielectric member and the electrode. A single-layer conductive film divided into portions is formed in the D area or on the side surfaces of the dielectric member, and a multilayer thin-film electrode is formed in the S area or on the end faces of the dielectric member. Conductive thin films of the multilayer thin-film electrode are alternately connected to the single-layer conductive film portions. In-phase currents having the same amplitude flow to the conductive thin films of the multilayer thin-film electrode in the S area in radial direction with respect to the axis of symmetry, thus achieving low-loss operation of the multilayer thin-film electrode in the S area.

Abstract: A conductive film is provided on a dielectric substrate. The conductive film has conductor opening portions, which serve as inductive regions, and a conductor opening portion, which serves as a capacitive region. Multi-step ring resonator elements, each including a conductor line aggregate, are provided on respective substrates to configure resonator elements. The resonator elements are mounted above the conductor opening portions that serve as the inductive regions. This arrangement provides a resonator having a high Qo.

Abstract: A resonator device including a plurality of resonance units formed on a dielectric substrate, each resonance unit having a plurality of conductor lines forming a capacitive area and an inductive area in a ring shape.

Abstract: A multi-spiral element includes a group of spiral conductive lines arranged so as not to cross each other so that the spiral conductive lines are substantially rotationally symmetric with respect to a predetermined point on a dielectric substrate. A plurality of conductive lines in the group of spiral conductive lines have external peripheral ends aligned at a substantially straight line substantially orthogonal to the group of spiral conductive lines. The external peripheral ends of each of the plurality of conductive lines in the multi-spiral element are connected to respective ends of a straight-line-group element having a group of parallel straight conductive lines. A resonator includes the multi-spiral elements functioning as capacitors for accumulating a charge, and the straight-line-group element functioning as an inductor.

Abstract: A dielectric resonator device comprising resonators small in size, having plural stages, and a dielectric resonator device with a high Qo, in a multimode are provided. A substantially parallelepiped-shaped dielectric core to resonate in plural modes such as TM01&dgr;-x, -y, -z, TE01&dgr;-x, -y, -z, and so forth is disposed in the center of a substantially parallelepiped-shaped cavity. These plural resonance modes are utilized.

Abstract: Ring-shaped resonant elements include respectively conductor lines 2a, 2b, and 2c each formed on a substrate 1 along a full one turn of circumferential length of a ring. Each of the conductor lines 2a, 2b, and 2c has two end portions which additionally extend and which are located such that they closely adjoin each other in a width direction. The respective ring-shaped resonant elements are disposed in a concentric fashion. Capacitive parts are formed in areas in which two ends of respective conductor lines are located in close proximity to each other, and the other parts of the respective conductor lines function as inductive parts. Each conductor line operates as a half-wave transmission line whose both ends are electrically open. It is not needed to form a ground electrode on a surface of the substrate opposite to the surface on which the conductor lines are formed. Thus, a resonator can be formed using a very small number of constituent elements.

Abstract: A high-frequency circuit device serving as a resonator includes a substrate and an electrode film which is formed on the surface of the substrate and which includes a conductive film and a dielectric film. The conductive film is formed around the substrate such that both ends of the conductive film overlap each other when viewed in a predetermined cross-section of the substrate, and the dielectric film is inserted between both ends of the conductive film. Accordingly, a self-capacitance portion is formed at the overlapped portion of the conductive film, electric-field energy is accumulated therein, and magnetic-field energy is accumulated inside the substrate. With this step impedance structure, the entire high-frequency circuit device can be miniaturized.

Abstract: A transmission line, a resonator, a filter, a duplexer, and a communication apparatus efficiently minimize power losses due to edge effects, thereby having superior loss-reduction characteristics. A continuous line and a plurality of thin lines each having a predetermined length and branching from both sides of the continuous line are formed on a dielectric substrate. With this structure, edges of the individual thin lines substantially do not exist, so that losses due to edge effects can be efficiently minimized.

Abstract: A transmission line, a resonator, a filter, a duplexer, and a communication apparatus efficiently minimize power losses due to edge effects, thereby having superior loss-reduction characteristics. A continuous line and a plurality of thin lines each having a predetermined length and branching from both sides of the continuous line are formed on a dielectric substrate. With this structure, edges of the individual thin lines substantially do not exist, so that losses due to edge effects can be efficiently minimized.

Abstract: A resonator includes a hollow dielectric element having a hole therein, a helical line unit including a plurality of helical lines formed in the hole, and a ground electrode formed on an outer surface of the dielectric element.