140results about "Multi-band filters" patented technology

The invention provides a composite high frequency component constituting a part of a microwave circuit having plural signal paths corresponding to their respective frequencies, comprising: a diplexer for coupling transmitting signals from the plural signal paths for transmission and distributing receiving signals into said plural signal paths for reception; plural high frequency switches for separating the plural signal paths into a transmission section and a reception section, respectively; plural filters introduced in the signal paths; said diplexer, said high frequency switch, and said filters being integrated into a ceramic multi-layer substrate formed by lamination of plural ceramic sheet layers. According to the above described composite high frequency component, the diplexer, the high frequency switches, and the filters which constitute the composite high frequency component are integrated into the ceramic multi-layer substrate formed by lamination of plural ceramic sheet layers. Thus, the matching and adjustment between the diplexer and the high frequency switches can be easily performed. It is unnecessary to provide a matching circuit for matching and adjusting the diplexer and the high frequency switches, and moreover, the high frequency switches and the filters.

PCT No. PCT / JP97 / 02660 Sec. 371 Date Jan. 20, 1999 Sec. 102(e) Date Jan. 20, 1999 PCT Filed Jul. 31, 1997 PCT Pub. No. WO98 / 05120 PCT Pub. Date Feb. 5, 1998A dual-band multilayer bandpass filter having a first filter unit (18) for filtering a first signal having a first frequency and a second filter unit (19) for filtering a second signal having a second frequency. First and second filter units are arranged in stacked ceramic layers. A first blocking element (20a, 20b; 25a, 25b; 25a', 25b'; 46a, 46b) is coupled to the first filter unit (18) for blocking the second signal from being applied to the first filter unit (18). A second blocking element (21a, 21b; 26a, 26b; 25c, 25d; 27a, 27b) is coupled to the second filter unit (19) for blocking the first signal from being applied to the second filter unit (19).

A composite high frequency component and a mobile communication apparatus incorporating the same which needs no matching circuits and can easily be miniaturized. The composite high frequency component is constituted of a diplexer, high frequency switches, high frequency filters, and surface acoustic wave filters. The diplexer is formed by first inductors and first capacitors. The high frequency switches are formed by diodes, second inductors, and second capacitors. The high frequency filters are formed by third inductors and third capacitors.

A filter circuit is constructed as a triplex filter having a high-pass filter, a low-pass filter with attenuation in the passband, and a second low-pass filter without attenuation in the passband. The filter circuit has a frequency response with a high-pass portion, a flat loss portion, and a low-pass portion. Attenuation in the flat loss portion is uniform and is predetermined via selection of filter components. The filter circuit is useful in a bidirectional CATV system in which performance is improved by selectable attenuation of a first source of return path signals but without attenuation of a second source of return path signals.

An apparatus is disclosed that includes a frequency multiplexer circuit coupled to an input node and configured to receive an input signal via the input node. The frequency multiplexer circuit comprises a first filter circuit, a second filter circuit, and a third filter circuit. The apparatus also includes a switching circuit that is configurable to couple at least two of a first output of the first filter circuit, a second output of the second filter circuit, or a third output of the third filter circuit to a single output port.

A wave filter is installed in a multimedia wideband router, and includes a circuit board having a first low-pass wave-filtering circuit, and a band-pass wave-filtering circuit; the band-pass wave-filtering circuit consists of a high-pass wave-filtering circuit and a second low-pass wave-filtering circuit; the first low-pass wave-filtering circuit is connected to the high-pass wave-filtering circuit; the circuit board further includes an input terminal, and a first switching component, which is movable to such a position as to electrically connect the input terminal and a joint between the first low-pass wave-filtering circuit and the high-pass wave-filtering circuit; the circuit board further includes two output terminals, which are connected to the first and the second low-pass wave-filtering circuits respectively; a second switching component is provided on the circuit board, which is movable to such a position as to electrically connect the high-pass wave-filtering circuit and the second low-pass wave-filtering circuit.

Circuitry, architectures, devices and systems for multi-band radio communications using a balanced-unbalanced duplexer. An integrated balanced-unbalanced duplexer for multi-band communications may include an unbalanced multi-band port; a first balanced single-band port; a second balanced single-band port; a first unbalanced coupling arm conductively coupled to the unbalanced multi-band port; a second unbalanced coupling arm conductively coupled to the unbalanced multi-band port; a first pair of balanced coupling arms conductively coupled to the first balanced single-band port and electromagnetically coupled to the first unbalanced coupling arm; and a second pair of balanced coupling arms conductively coupled to the second balanced single-band port and electromagnetically coupled to the second unbalanced coupling arm. The architectures and / or systems generally include components embodying one or more of the concepts disclosed herein.

A duplexer and a communication apparatus incorporating the same which are suitable for use in communication systems with wide frequency bands and narrow separations, and which can be miniaturized while having satisfactory characteristics. The duplexer has a transmission filter constituted of a variable frequency filter in which PIN diodes are connected to dielectric resonators and a reception filter constituted of two surface acoustic wave filters and a switching circuit. In the transmission filter, one of the higher and lower sides of a transmission frequency band can be selected according to a voltage applied to a first voltage control terminal. In addition, in the reception filter, one of the two surface acoustic wave filters can be selected according to a voltage applied to a second voltage control terminal.

The present disclosure relates to a passive multi-band duplexer having a first bandpass filter and a second bandpass filter. The first bandpass filter includes a first group of sub-band bandpass filters, a first switching circuit, and a first tunable LC bandpass filter. Similarly, the second bandpass filter includes a second group of sub-band bandpass filters, a second switching circuit, and a second tunable LC bandpass filter. A first band of the passive multi-band duplexer, such as a transmit band, is chosen by selecting one of the first group of sub-band bandpass filters and tuning the first tunable LC bandpass filter to the first band. Similarly, a second band of the passive multi-band duplexer, such as a receive band, is chosen by selecting one of the second group of sub-band bandpass filters and tuning the second tunable LC bandpass filter to the second band.

The disclosed is a downsized and power saving antenna duplexer. The antenna duplexer includes: diplexer; first surface acoustic wave filter to transmit / receive low channel frequency band signals; first phase shift circuit to match the transmission phase with the reception phase of first surface acoustic wave filter; second surface acoustic wave filter to transmit / receive high channel frequency band signals; second phase shift circuit to match the transmission phase with the reception phase of second surface acoustic wave filter. Diplexer, first phase shift circuit and second phase shift circuit are formed in a monolithic structure in package that includes surface acoustic wave filters. The configuration can provide the antenna duplexer with a compact size, a lower current consumption and a highly efficient performance.

Gain setting can be performed at high speed while reducing DC offset due to a filter cutoff frequency changeover without the need for input signal muting. A filter circuit having first and second filters is capable of allowing settings of first and second cutoff frequencies. First and second filter switch circuits and a charging circuit including a charging resistor and a charging switch are provided. For a first time period, the first switch circuit is controllably turned on while the second switch circuit is controllably turned off, thereby providing the first filter function. For a second time period, the first switch circuit is controllably turned off while the second switch circuit is controllably turned on, thereby providing the second filter function. For the first time period, the charging switch is controllably turned on so that the second capacitor is charged via the charging resistor.

A system and method integrates signal filters in a multiband transceiver. A preferred embodiment comprises an amplifier with a first tunable capacitor coupled to a signal input and a tunable filter. The tunable filter comprises an input stage with a first pair of inductors arranged in a dipole configuration and a second tunable capacitor coupled in parallel to the first pair of inductors and an output stage inductively coupled to the input stage, the output stage includes a second pair of inductors also arranged in a dipole configuration and a third tunable capacitor coupled in parallel to the second pair of inductors. The inductors are realized using bond wire or any other high Q material. The first tunable capacitor, the second tunable capacitor, and the third tunable capacitor can be tuned using a master-slave tuning configuration to adjust the operating frequency of the amplifier and the tunable filter to enable frequency band compatibility with multiple communications protocols.

A matching device causes an antenna to match a receiving section arranged to receive a signal in a first frequency band and a signal in a second frequency band lower than the first frequency band. The matching device includes a first terminal arranged to be connected to the antenna, a first inductor connected between the first terminal and a first node, a second inductor connected between the first node and a ground, a first capacitor connected between the first node and a second node, a second terminal arranged to be connected to the receiving section, the second terminal being connected to the second node, and a third inductor connected between the second node and the ground. The second inductor has a capacitive impedance in the first frequency band, and has an inductive impedance in the second frequency band. This matching device can supply a signal in the second frequency band received by the antenna to the receiving section with a small loss. The antenna having a small length can receive a signal of low frequencies and long wavelengths in the second frequency band.

An acoustic wave filter apparatus includes first and second acoustic wave filter sections on one piezoelectric substrate, first balance terminals of the first and second acoustic wave filter sections are commonly coupled to each other, and second balance terminals thereof are commonly coupled to each other. An acoustic wave filter apparatus where first balance input / output terminals of first and second acoustic wave filter sections are commonly connected to each other and then connected to a first balance terminal, second balance input / output terminals thereof are commonly connected to each other and then connected to a second balance terminal, the first and second balance output terminals of the first acoustic wave filter section are connected to first and third acoustic wave resonators, respectively, via first and third wiring lines, respectively, and then coupled to the first and second balance terminals, respectively, via the first and third acoustic wave resonators, respectively, the first and second balance output terminals of the second acoustic wave filter section are coupled to the first and second balance terminals, respectively, via second and fourth wiring line and second and fourth acoustic wave resonators, respectively, and the second wiring line and second wiring line cross each other on a piezoelectric substrate.

A high-frequency composite component for selectively switching a GSM-system signal path and a DCS-system signal path for a signal transmitted to or received from an antenna terminal by a diplexer. Transmission-side input terminals and reception-side balanced output terminals to be switched by high-frequency switches are included in the GSM and the DCS systems. Matching elements include inductors and capacitors that are inserted between the reception-side balanced output terminals and the output side of surface acoustic wave filters.

A radio frequency (RF) hybrid switch module includes an antenna duplexer integrated with a surface acoustic wave (SAW) filter used in a mobile communication device such as a cellular phone. The switch module handles a transmitted signal and received signal of different frequency bands. A parasitic inductance due to a mounting of the SAW filter is reduced, so that an attenuation characteristic at a low frequency of the SAW filter is improved. The RF hybrid switch module includes: a dividing circuit; a switching circuit; a low pass filter (LPF); an electrode for forming at least a portion of the dividing circuit, switching circuit, and the LPF; a laminated body including a dielectric layer having the electrode formed thereon; a SAW filter which is mounted on the laminated body, corresponds to plural frequency bands, and has a grounding port; a diode mounted on the laminated body for forming a portion the switching circuit, a grounding electrode formed in the laminated body, and a via-conductor directly connecting the grounding port of the SAW filter.

A plurality of surface acoustic wave filters having different center frequencies is provided on a piezoelectric substrate. Either input terminals or output terminals, or both input terminals and output terminals of the surface acoustic wave filters are integrated. Of the surface acoustic wave filters, a surface acoustic wave filter having a higher center frequency is configured so as to suppress a spurious response in the proximity of the high-frequency side in or outside a passband in the filter characteristics of a surface acoustic wave filter having a lower center frequency, for example, such that the width or pitch of electrode fingers in at least one region of reflectors differs from that in other regions.

A composite high frequency component, comprising: a first high frequency switch having a first common port and firsts second, and third communication ports, wherein: the first communication port is operable to connect to respective transmitting sections of first and second communication systems which operate in substantially the same frequency band, the second communication port is operable to connect to a receiving section of the first communication system, the third communication port is operable to connect to a receiving section of the second communication system, and the first high frequency switch has a transfer characteristic for passing signals between the first common port and the first, second and third communication ports which are in the frequency band of the first and second communication systems as a function of at least one first control signal; a second high frequency switch having a second common port and fourth and fifth communication ports, wherein: the fourth communication port is operable to connect to a transmitting section of a third communication system which operates in a different frequency band than the first and second communication systems, the fifth communication port is operable to connect to a receiving section of the third communication system, and the second high frequency switch has a transfer characteristic for passing signals between the second common port and the fourth and fifth communication ports which are in the frequency band of the third communication system as a function of at least one second control signal; a first filter having a transfer characteristic for passing signals in the frequency band of the first and second communication systems, one end of the first filter being coupled to the first common port of the first high frequency switch; a second filter having a transfer characteristic for passing signals in the frequency band of the third communication system, one end of the second filter being coupled to the second common port of the second high frequency switch; and a diplexer having a third common port and first and second input / output ports, wherein: the third common port is operable to at least one of receive and transmit signals from an antenna, the first input / output port is coupled to an opposite end of the first filter, the second input / output port is coupled to an opposite end of the second filter, and the diplexer has a transfer characteristic for passing signals: (i) between the third common port and the first input / output port which are in the frequency band of the first and second communication systems, and (ii) between the third common port and the second input / output port which are in the frequency band of the third communication system.

A radio-frequency module includes switch elements, first signal paths, band pass filters, first matching circuits, second signal paths, and second matching circuits. Each of the first signal paths is connected between one end of a corresponding one of the switch elements and an antenna terminal. Each of the band pass filters is connected to a corresponding one of the first signal paths and allows a radio-frequency signal of one of the plurality of frequency bands to pass therethrough. Each of the first matching circuits is connected to a corresponding one of the first signal paths. Each of the second signal paths is connected to a corresponding one of the switch elements. Each of the second matching circuits is connected to a corresponding one of the second signal paths. A component included in the first matching circuits and a component included in the second matching circuits are electromagnetically coupled.

A duplexer includes two surface acoustic wave filter having different band center frequencies, and a phase matching circuit that matches the phases of the two surface acoustic wave filters to each other. In this duplexer, one of the two surface acoustic wave filters is a ladder type surface acoustic wave filter, while the other one of the two surface acoustic wave filters includes two or more dual-mode type surface acoustic wave filters that are connected in parallel.

An electronic filter comprises a housing having input and output ends. The housing has a body and a connector. The connector is located at the input end of the housing. A circuit board is located within the body. A collet assembly is located within the connector to receive electrical signals and conduct them to the circuit board. The collet assembly includes an insulator, a conductor, and an elastomeric sealing member. The insulator is located within the connector. The insulator contains a generally cylindrical opening through its length. The conductor extends through the opening of the insulator. The conductor has an input end adjacent the input end of the housing and an output end adjacent the circuit board. The conductor has a hollow interior at its input end. The sealing member surrounds the insulator in compressed engagement with the insulator and the surrounding connector.

A noise filter connected to an LC oscillator is provided. The noise filter comprises a transmission line, a DC bias circuit, and a capacitor. The transmission line is connected to the LC oscillator. The DC bias circuit is connected to the transmission line and provides a bias current. The capacitor has one end connected between the transmission line and the DC bias circuit and the other end AC grounded and provides a path to AC ground to the transmission line. A length of the transmission line is odd times that of a quarter-wavelength of a secondary harmonic wave of the LC oscillator.