17results about "Multi-band filters" patented technology

An acoustic wave filter package is disclosed. The acoustic wave filter package can include a first acoustic wave filter, a second acoustic wave filter, and a shared node. The first acoustic wave filter is configured to filter a first radio frequency signal. The first acoustic wave filter has a first shunt resonator. The second acoustic wave filter is configured to filter a second radio frequency signal. The second acoustic wave filter having a second shunt resonator. The first and second shunt resonators are electrically coupled to ground at the shared node.

A multi-band acoustic multiplexer filter circuit is provided. The multi-band acoustic multiplexer filter circuit includes multiple single-band acoustic filters and a multi-band filter circuit that can pass a signal in multiple passbands. In embodiments disclosed herein, the single-band acoustic filters and the multi-band filter circuit can be configured to collectively attenuate the signal in some of the passbands to thereby prevent the signal from becoming a blocking signal to any other passbands (e.g., adjacent passbands). By employing the multi-band filter circuit to provide a portion of the required attenuation to the blocking signal, each of the single-band acoustic filters can be subject to more relaxed attenuation requirements, thus making it possible to reduce complexity of the single-band acoustic filters and improve overall band rejection performance of the multi-band acoustic multiplexer filter circuit.

The invention provides a method and equipment for determining amplitude gains of sub-band filters in a graphic equalizer, and the method comprises the steps: determining the center frequency, bandwidth and initial amplitude gain of each sub-band filter in the graphic equalizer, and inputting an initial signal into all sub-band filters, obtaining a sub-band response signal which is output by each sub-band filter and corresponds to each center frequency and bandwidth, obtaining a difference value between each sub-band response signal and a preset target response signal, taking the difference value as an element to obtain a mutual influence matrix, and correcting the initial amplitude gain of each sub-band filter by an inverse matrix of the mutual influence matrix to obtain a sub-band response signal; according to the scheme of the invention, the method can eliminate the mutual influence between different sub-band filters through the change of the amplitude gain of each sub-band filter, and a final filtering result is higher in precision.

Embodiments of resonator circuits and modulating resonators and are described generally herein. One or more acoustic wave resonators may be coupled in series or parallel to generate tunable filters. One or more acoustic wave resonances may be modulated by one or more capacitors or tunable capacitors. One or more acoustic wave modules may also be switchable in a filter. Other embodiments may be described and claimed.

An example resonating structure comprises a substrate, a resonator body, and an anchoring body for anchoring the resonator body to the substrate. The resonator body is doped with a dopant having a concentration chosen so as to minimize a second order temperature coefficient of frequency for the resonator body. The resonator body is operable in an in-plane mode of vibration and an out-of-plane mode of vibration.

A multi-band filter configured to allow signals to pass at multiple frequency bands includes a piezoelectric substrate and a plurality of groups of electrodes disposed on the piezoelectric substrate. Each group forms a respective filter to allow signals to pass at a corresponding frequency band. A first group forms a first filter having a first frequency band and a second group forms a second filter having a second frequency band. The first frequency band is lower than the second frequency band. The filter includes a dielectric film formed to cover at least a part of the piezoelectric substrate and the plurality of groups of electrodes. The filter also includes a passivation film disposed on the dielectric film. The passivation film has a smaller thickness for the first group than for the second group, so as to suppress a spurious response generated in the piezoelectric substrate.

A bandpass filter (1) includes: an input terminal (2A) to which a high-frequency signal is input; an output terminal (2B) from which an output signal is output; differential switches (4 to 9) provided between the input terminal (2A) and the output terminal (2B), in which a plurality of switches (10 to 21) controlled by a clock signal are connected in a tournament type, each of which comprises two switches; and capacitors (22 to 25), one end of which is connected to a connection point of a switch between the differential switches, and the other end of which is grounded.

A Lamb wave filter is provided which has improved out of band rejection, the filter including a substrate having a center region and two edge regions, a first set of electrodes arranged as a first interdigital transducer displaced on one of the two edge regions and configured to receive an input signal, a second set of electrodes arranged as a second interdigital transducer displaced on the other of the two edge regions and configured to provide a filtered output signal, and a third set of electrodes disposed parallel to the first and second sets of electrodes on the center region of the substrate.

A surface acoustic wave filter is disclosed. The surface acoustic wave filter includes a substrate, and first and second surface acoustic wave filter structures disposed on first and second main surfaces of the substrate, respectively. The first surface acoustic wave filter structure includes a first piezoelectric layer a plurality of first surface acoustic wave resonators formed on a top surface of the first piezoelectric layer, and a first wiring layer connecting the first surface acoustic wave resonators to each other. The second surface acoustic wave filter structure includes a second piezoelectric layer, a plurality of second surface acoustic wave resonators formed on a bottom surface of the second piezoelectric layer, and a second wiring layer connecting the second surface acoustic wave resonators to each other. A plurality of through electrodes extends through the substrate, the first piezoelectric layer, and the second piezoelectric layer. A circuit including the first surface acoustic wave resonators and the first wiring layer on the top surface of the first piezoelectric layer forms at least one first radio frequency filter, and a circuit including the plurality of second surface acoustic wave resonators and the second wiring layer on the bottom surface of the second piezoelectric layer forms at least one second radio frequency filter. The at least one first radio frequency filter and the at least one second radio frequency filter belong to different frequency bands.

Embodiments of resonator circuits and modulating resonators and are described generally herein. One or more acoustic wave resonators may be coupled in series or parallel to generate tunable filters. One or more acoustic wave resonances may be modulated by one or more capacitors or tunable capacitors. One or more acoustic wave modules may also be switchable in a filter. Other embodiments may be described and claimed.

To provide a wide-bandwidth resonant circuit.SOLUTION: In an embodiment disclosed herein, the wide-bandwidth resonant circuit includes a positive resonant circuit coupled in parallel to a negative resonant circuit. The positive resonant circuit and the negative resonant circuit can be configured to collectively exhibit certain impedance characteristics across a wide bandwidth. As a result, it is possible to utilize the wide-bandwidth resonant circuit to support a variety of wide-bandwidth applications, e.g., in a wide-bandwidth signal filter circuit.SELECTED DRAWING: Figure 1

A method of manufacturing a packaged surface acoustic wave filter chip is disclosed. The method can include providing a structure having first interdigital transducer electrodes formed with a first piezoelectric layer, second interdigital transducer electrodes formed with a second piezoelectric layer, and a substrate between the first and second piezoelectric layers. The method can include forming a plurality of through electrodes extending at least partially through a thickness of the structure such that a first set of through electrodes of the plurality of through electrodes are electrically connected to the first interdigital transducer electrodes and a second set of through electrodes of the plurality of through electrodes are electrically isolated from the first interdigital transducer electrodes.

The band-pass filter (1) comprises an input terminal (2A) to which a high-frequency signal is input, an output terminal (2B) from which an output signal is output, a plurality of switches (10-21) connected in a tournament configuration between the input terminal (2A) and the output terminal (2B) and controlled by a clock signal, differential switches (4-9) each consisting of two switches, and capacitances (22-25) having one end connected to a connection point between the differential switches and the other end grounded.

A multi band filter package is disclosed. The multi band filter can include a first acoustic wave filter that is mounted on a carrier, a second acoustic wave filter mounted on the carrier, and a ground pad on the carrier. The first acoustic wave filter has a first filter component and a first shunt resonator. The second acoustic wave filter has a second filter component and a second shunt resonator. The first and second acoustic wave filters are arranged such that the first and second shunt resonators are positioned between the first and second filter component. The first and second shunt resonators are coupled to the ground pad by way of an electrically conductive path. A least a portion of the electrically conductive path is positioned between the first and second shunt resonators.

Communication device (300), comprising: a triplexer (320, 400, 1100) with a common port and first, second and third branching ports; the triplexer includes (320, 400, 1100): a hybrid inductor-capacitor / surface acoustic wave (LC / SAW) high-pass filter (410, 600, 700) coupled between the common port (Com.) and the third branching port (B3); a hybrid (LC / SAW) low-pass filter (420, 800, 900, 1000) coupled between the common port (Com.) and an internal node; an LC high-pass filter (430, 1130) coupled between the internal node and the second branching port (B2); an LC low-pass filter (440, 1140) coupled between the internal node and the first branching port (B1).

A multi band filter package is disclosed. The multi band filter can include a first acoustic wave filter that is mounted on a carrier, a second acoustic wave filter mounted on the carrier, and a ground pad on the carrier. The first acoustic wave filter has a first filter component and a first shunt resonator. The second acoustic wave filter has a second filter component and a second shunt resonator. The first and second acoustic wave filters are arranged such that the first and second shunt resonators are positioned between the first and second filter component. The first and second shunt resonators are coupled to the ground pad by way of an electrically conductive path. At least a portion of the electrically conductive path is positioned between the first and second shunt resonators.

A multi-band filter configured to allow signals to pass at multiple frequency bands includes a piezoelectric substrate and a plurality of groups of electrodes disposed on the piezoelectric substrate. Each group forms a respective filter to allow signals to pass at a corresponding frequency band. A first group forms a first filter having a first frequency band and a second group forms a second filter having a second frequency band. The first frequency band is lower than the second frequency band. The filter includes a dielectric film formed to cover at least a part of the piezoelectric substrate and the plurality of groups of electrodes. The filter also includes a passivation film disposed on the dielectric film. The passivation film has a smaller thickness for the first group than for the second group, so as to suppress a spurious response generated in the piezoelectric substrate.