Abstract: The present invention relates to a high frequency laminated component, which is used in a high frequency apparatus such as a radio communication apparatus, and its manufacturing method. An object thereof is to downsize the high frequency laminated component. To achieve the object, according to the high frequency laminated component of the present invention, dielectric layer (4) whose dielectric constant is lower than that of other areas is formed around via-hole electrode (3) in a dielectric. By forming dielectric layer (4) having a low dielectric constant, electric interference between via-hole electrode (3) and circuit electrode (22) is restrained, so that the circuit electrode and the via-hole electrode can be formed more closely each other compared with a conventional one. As a result, the high frequency laminated component can be downsized.

Abstract: A surface acoustic wave (SAW) filter includes a first SAW resonator, a second SAW resonator connected in series to the first SAW resonator at a first node, a third SAW resonator connected in series to the second SAW resonator at a second node, a fourth SAW resonator connected in series to the third SAW resonator at a third node, a fifth SAW resonator connected between the first node and ground, a sixth SAW resonator connected between the third node and ground, and a first capacitance element connected between the second node and ground. Further, the SAW filter includes a first inductance element connected in series to the fifth SAW resonator, and a second inductance element connected in series to the sixth SAW resonator. This SAW filter has a sharp attenuation at a high frequency of a pass band, thereby widening the pass band and reducing the loss thereof.

Abstract: A surface acoustic wave filter having a plurality of the transmission lines, each with one end connected to the surface acoustic wave element and the other end thereof connected to a ground. The transmission lines are divided by an additional transmission line which has multiple connections to a ground electrode at an interval equal to or lower than a wavelength of a using frequency. This structure provides grounds among a plurality of transmission lines and thus isolation among terminals can be increased to improve the filter characteristic.

Abstract: A laminated dielectric filter is formed by coupling a plurality of resonators to one another by electromagnetic-field coupling. In the laminated dielectric filter, a bypass circuit formed of a series circuit including bypass capacitors and transmission lines is provided in parallel to a magnetic-field bypass coupling between non-adjacent resonators. Thus, capacitance of the bypass capacitors can be regulated without being affected by the magnetic-field bypass coupling between the non-adjacent resonators. As a result, attenuation poles outside a passband can be controlled freely.

Abstract: A surface acoustic wave filter having at least one transmission line of which one end of a plurality of the transmission lines is connected to the surface acoustic wave element and the other end thereof is connected to a ground, and the transmission lines being divided by a transmission line which is connected to a ground electrode at an interval equal to or lower than a wavelength of a using frequency. This structure provides grounds among a plurality of transmission lines and thus isolation among terminals can be increased to improve the filter characteristic.

Abstract: A high-frequency hybrid switch module arranged applicable to at least two different communications systems includes two low pass filters (LPFs), two phase shifters, a field effect transistor (FET) switch including FETs, and two SAW filters. The FETs and the SAW filters are mounted on a layered assembly including the LPFs and an electrode pattern of the phase shifters. The module can have a small overall size, a low cost, and a small loss, while being protected from static electricity. The module requires small number of low-noise amplifiers at a signal receiving side.

Abstract: A high frequency composite switch module for a mobile communication device, wherein high frequency circuits such as a power amplifier, a circuit functioning as a transmitter/receiver switching circuit, a surface acoustic wave (SAW) filter for reception, and the like are modularized into one unit. A transmitter circuit includes a transmitter side impedance converter comprising an impedance matching circuit and an impedance converter circuit, a power amplifier and a power supply unit. A receiver circuit includes a receiver-side impedance converter comprising a phase shifting circuit and a SAW filter. The power amplifier and the impedance converter circuit are integrated into one IC chip. At least one of the matching circuit, the power supply unit and the phase shifting circuit is formed inside a multilayer board comprised of a conductor layer and a dielectric layer. The IC chip and the SAW filter are also mounted on the multilayer board.

Abstract: A surface acoustic wave (SAW) filter includes a first SAW resonator, a second SAW resonator connected in series to the first SAW resonator at a first node, a third SAW resonator connected in series to the second SAW resonator at a second node, a fourth SAW resonator connected in series to the third SAW resonator at a third node, a fifth SAW resonator connected between the first node and a ground, a sixth SAW resonator connected between the third node and a ground, and a first capacitance element having a capacitance and connected between the second node and a ground. This SAW filter has a sharp attenuation characteristic at a high frequency area of a pass band, thereby widening the pass band and reducing a loss at the pass band.

Abstract: A frequency switch is configured with two FET switches. One end of a second FET switch is connected between an I/O port and a reception port and the other end is ground. A strip line is connected between the second FET switch and the I/O port, and has an electrical length equivalent to ¼ wavelength of a high frequency signal input from transmission port.

Abstract: A high frequency switch configured particularly with FET switches. One end of second FET switch is connected between I/O port and reception port and the other end is ground. A parallel unit of strip line and capacitor is connected between second FET switch and I/O port. This parallel unit has the electrical length equivalent to ¼ wavelength of the high frequency signal input from transmission port.

Abstract: A surface acoustic wave (SAW) filter includes an input terminal, an output terminal, a series resonator provided between the input terminal and the output terminal, first and second parallel resonators having respective one ports connected to respective ports of the series resonator, respectively, first and second nodes connected to respective other ports of the first and second parallel resonators, respectively, first and second inductance elements having respective one ends connected to the first and second nodes, respectively, a third node connected to respective other ends of the first and second inductance elements, a third inductance element having one end connected to the third node, a grounding terminal connected to other end of the third inductance element, and a capacitance element connected between the first and second nodes. The SAW filter has a large attenuation amount at a lower side of a pass band of the filter, thus having sufficient properties.

Abstract: A surface acoustic wave filter with little electromagnetic coupling between wires and improved attenuation characteristics is provided. This surface acoustic wave filter comprises: a package having a concavity in the shape of stairs made by laminating dielectrics, a surface acoustic wave element provided on the bottom face of the concavity, a plurality of wires for connecting between a plurality of electrodes provided on the surface of the surface acoustic wave element and a plurality of electrodes provided on one same plane portion of the stairs of the package in correspondence to a plurality of electrodes, and a dummy wire provided between the wires.

Abstract: A high frequency switch module can handle transmit-receive signals of different frequency bands and realize excellent isolation. The high frequency switch module comprises a discriminating filter, a low-band high frequency switch, and a high-band frequency switch, wherein high-band 90-degree phase shifter that forms at least a high-band high frequency switch is configured by a high-pass filter, and a choke line is parallel-connected to the high-pass filter.

Abstract: The present invention relates to a high frequency laminated component, which is used in a high frequency apparatus such as a radio communication apparatus, and its manufacturing method. An object thereof is to downsize the high frequency laminated component. To achieve the object, according to the high frequency laminated component of the present invention, dielectric layer (4) whose dielectric constant is lower than that of other areas is formed around via-hole electrode (3) in a dielectric. By forming dielectric layer (4) having a low dielectric constant, electric interference between via-hole electrode (3) and circuit electrode (22) is restrained, so that the circuit electrode and the via-hole electrode can be formed more closely each other compared with a conventional one. As a result, the high frequency laminated component can be downsized.

Abstract: A bias circuit is provided for attenuating harmonic distortions of a signal having a simple construction and which can be applied to a high-frequency amplifier used in a communication device, such as a mobile telephone. The circuit reduces a voltage drop therein and thus provides a high-frequency amplifier having reduced power consumption and an increased operating efficiency. The high-frequency amplifier includes an amplifier circuit, an output matching circuit, and the bias circuit. In the bias circuit, a parallel circuit including a first transmission line and a first capacitor has one end connected between the amplifier and the output matching circuit. The other end of the parallel circuit is connected to a power source and is grounded via a second capacitor. In the circuit, the bias circuit can be short-circuited in a desired frequency band while being an open circuit in a frequency band of a signal to be amplified, hence attenuating the harmonic distortions without using a low pass filter.

Abstract: A high frequency switch module can handle transmit-receive signals of different frequency bands and realize excellent isolation. The high frequency switch module comprises a discriminating filter, a low-band high frequency switch, and a high-band frequency switch, wherein high-band 90-degree phase shifter that forms at least a high-band high frequency switch is configured by a high-pass filter, and a choke line is parallel-connected to the high-pass filter.

Abstract: A high frequency switch configured particularly with FET switches. One end of second FET switch is connected between I/O port and reception port and the other end is ground. A parallel unit of strip line and capacitor is connected between second FET switch and I/O port. This parallel unit has the electrical length equivalent to ¼ wavelength of the high frequency signal input from transmission port.

Abstract: A dielectric filter including a plurality of resonators, and at least one transmissions line provided among said plurality of resonators. A band rejection characteristic is formed around a resonance frequency of said resonator, and a line length of said transmission line is shorter than ¼ of a wavelength corresponding to the resonance frequency of said resonator.

Abstract: A surface acoustic wave (SAW) filter includes an input terminal, an output terminal, a series resonator provided between the input terminal and the output terminal, first and second parallel resonators having respective one ports connected to respective ports of the series resonator, respectively, first and second nodes connected to respective other ports of the first and second parallel resonators, respectively, first and second inductance elements having respective one ends connected to the first and second nodes, respectively, a third node connected to respective other ends of the first and second inductance elements, a third inductance element having one end connected to the first node, a grounding terminal connected to other end of the third inductance element, and a capacitance element connected between the first and second nodes. The SAW filter has a large attenuation amount at a lower side of a pass band of the filter, thus having sufficient properties.

Abstract: A high frequency composite switch module for a mobile communication device, wherein high frequency circuits such as a power amplifier, a circuit functioning as a transmitter/receiver switching circuit, a surface acoustic wave (SAW) filter for reception, and the like are modularized into one unit. A transmitter circuit includes a transmitter side impedance converter comprising an impedance matching circuit and an impedance converter circuit, a power amplifier and a power supply unit. A receiver circuit includes a receiver-side impedance converter comprising a phase shifting circuit and a SAW filter. The power amplifier and the impedance converter circuit are integrated into one IC chip. At least one of the matching circuit, the power supply unit and the phase shifting circuit is formed inside a multilayer board comprised of a conductor layer and a dielectric layer. The IC chip and the SAW filter are also mounted on the multilayer board.