Abstract: Certain aspects of the present disclosure provide a filter circuit and techniques for filtering using the filter circuit. The filter circuit generally includes a first filter stage having a first acoustic wave resonator coupled in a series path between a first port of the filter circuit and a second port of the filter circuit, a first inductor-capacitor (LC) tank circuit, a first capacitor coupled between a first terminal of the first acoustic wave resonator and the first LC tank circuit, the first LC tank circuit being coupled between the first capacitor and a reference potential node, and a second capacitor coupled between a second terminal of the first acoustic wave resonator and the first LC tank circuit. In some aspects, the filter circuit includes one or more other filter stages coupled to the first filter stage.

Abstract: Certain aspects of the present disclosure provide a filter circuit and techniques for filtering using the filter circuit. The filter circuit generally includes a first filter stage having a first acoustic wave resonator coupled in a series path between a first port of the filter circuit and a second port of the filter circuit, a first inductor-capacitor (LC) tank circuit, a first capacitor coupled between a first terminal of the first acoustic wave resonator and the first LC tank circuit, the first LC tank circuit being coupled between the first capacitor and a reference potential node, and a second capacitor coupled between a second terminal of the first acoustic wave resonator and the first LC tank circuit. In some aspects, the filter circuit includes one or more other filter stages coupled to the first filter stage.

Abstract: In an example, an apparatus includes first and second antennas and a switched extractor coupled to the first antenna. The switched extractor includes an extractor configured to extract an extraction frequency band, a bypass line, and switching circuitry. The switching circuitry is configured to selectively establish a bypass signal path including the bypass line or a concurrent signal path including the extractor. The apparatus also includes first and second transceiver units (TRXUs) and a processor. The first TRXU is coupled to the first antenna via the switched extractor. The second TRXU is coupled to the first antenna via the switched extractor and coupled to the second antenna. The processor is configured to cause the switching circuitry to selectively connect the first TRXU to the first antenna via the bypass or the concurrent signal path based on the extraction frequency band and an operational frequency band associated with the first TRXU.

Abstract: A filter device having a reduced sensitivity to production tolerances comprises a multilayer panel with integrated wiring, a piezoelectric substrate mounted to the panel. A first filter circuit (FC1) and a signal path (SP) comprising a second filter circuit are realized on the substrate and connected to a common antenna terminal (AT) as well as to a common node (CN) located on top of the piezoelectric substrate. A first matching circuit (MC1) and further matching circuits (MC2) are realized by the wiring in the multilayer panel.

Abstract: In an example, an apparatus includes first and second antennas and a switched extractor coupled to the first antenna. The switched extractor includes an extractor configured to extract an extraction frequency band, a bypass line, and switching circuitry. The switching circuitry is configured to selectively establish a bypass signal path including the bypass line or a concurrent signal path including the extractor. The apparatus also includes first and second transceiver units (TRXUs) and a processor. The first TRXU is coupled to the first antenna via the switched extractor. The second TRXU is coupled to the first antenna via the switched extractor and coupled to the second antenna. The processor is configured to cause the switching circuitry to selectively connect the first TRXU to the first antenna via the bypass or the concurrent signal path based on the extraction frequency band and an operational frequency band associated with the first TRXU.

Abstract: Transmission-line filtering with enhanced frequency response is disclosed. In an example aspect, an apparatus includes a transmission-line filter to enhance a frequency response of a filtering operation. The transmission-line filter includes an input port, an output port, and multiple transmission-line base units. The multiple transmission-line base units are disposed between the input port and the output port and are coupled to the input port and the output port. Each of the multiple transmission-line base units includes a respective transmission line of multiple transmission lines. At least one transmission-line base unit of the multiple transmission-line base units includes a multi-resonant circuit.

Abstract: A filter and a method for forming a filter are disclosed. In an embodiment a filter includes a first port, a second port and a signal path between the first port and the second port. The filter further includes a plurality of series resonators electrically connected in series in the signal path, a plurality of shunt paths, each electrically connecting the signal path to ground and one parallel resonator electrically connected in each shunt path, wherein at least one series resonator is an electroacoustic resonator, and wherein at least one parallel resonator comprises one acoustically inactive capacitor or an electrical connection of an acoustically active resonator and a de-tuning coil.

Abstract: Transmission-line filtering with enhanced frequency response is disclosed. In an example aspect, an apparatus includes a transmission-line filter to enhance a frequency response of a filtering operation. The transmission-line filter includes an input port, an output port, and multiple transmission-line base units. The multiple transmission-line base units are disposed between the input port and the output port and are coupled to the input port and the output port. Each of the multiple transmission-line base units includes a respective transmission line of multiple transmission lines. At least one transmission-line base unit of the multiple transmission-line base units includes a multi-resonant circuit.

Abstract: An integrated passive device transmission-line resonator is disclosed herein. An example structure of the transmission-line resonator includes a glass substrate having first and second sides, a ground plane, a dielectric layer, and features fabricated from two metal layers. A first metal layer, which is formed on the second side of the glass substrate, includes a first capacitor plate and a conductor that, in conjunction with a portion of the ground plane, realizes a transmission line. A portion of the dielectric layer is disposed between the first capacitor plate and a second capacitor plate, which is formed from a second metal layer and positioned axially above the first capacitor plate, to form a capacitor. A smooth interface between a surface of the second side of the glass substrate and the conductor reduces transmission losses of signals propagating across the transmission line and increases performance of the transmission-line resonator.

Abstract: In an example, an apparatus includes first and second antennas and a switched extractor coupled to the first antenna. The switched extractor includes an extractor configured to extract an extraction frequency band, a bypass line, and switching circuitry. The switching circuitry is configured to selectively establish a bypass signal path including the bypass line or a concurrent signal path including the extractor. The apparatus also includes first and second transceiver units (TRXUs) and a processor. The first TRXU is coupled to the first antenna via the switched extractor. The second TRXU is coupled to the first antenna via the switched extractor and coupled to the second antenna. The processor is configured to cause the switching circuitry to selectively connect the first TRXU to the first antenna via the bypass or the concurrent signal path based on the extraction frequency band and an operational frequency band associated with the first TRXU.

Abstract: The invention relates to an electronic structural element (1) with a first and a second base plate (2a, 2b), as well as a coupling plate (3), wherein, between the first base plate (2a) and the coupling plate (3), a first electrical capacitor (C1) is formed, and, between the second base plate (2b) and the coupling plate (3), a second electrical capacitor (C2) is formed, so that the first and the second electrical capacitors (C1, C2) form an electrical series capacitor (Cs) between the first and the second base plates (2a, 2b). According to the invention, the coupling plate (3) is divided into a plurality (N) of mutually non-contacting strips (6), wherein the first and the second electrical capacitors (C1, C2) are in each case divided into a plurality (N) of electrical elementary capacitors (Ce), and, by means of the strips (6), a plurality (N) of parallel-connected, electrical elementary series capacitors (Cse) is formed between the first and the second base plates (2a, 2b).

Abstract: A filter and a method for forming a filter are disclosed. In an embodiment a filter includes a first port, a second port and a signal path between the first port and the second port. The filter further includes a plurality of series resonators electrically connected in series in the signal path, a plurality of shunt paths, each electrically connecting the signal path to ground and one parallel resonator electrically connected in each shunt path, wherein at least one series resonator is an electroacoustic resonator, and wherein at least one parallel resonator comprises one acoustically inactive capacitor or an electrical connection of an acoustically active resonator and a de-tuning coil.

Abstract: A multiband circuit includes a signal path comprising a first signal branch that includes a first circuit that is transmissive in a first frequency band and a second signal branch that includes a second circuit that is transmissive in a second frequency band. The first and second signal branches are combined on an antenna side into a common path.

Abstract: A ceramic multilayer construction includes three resonators designed as parallel strip lines that are capacitatively or magnetically coupled to each other. All circuit components are implemented in the form of metallizations in multilayer construction. Capacitative couplings are implemented by coupling capacitors. The strip line resonators are shortened by shunt arms to ground having grounding capacitors arranged therein.

Abstract: A bandpass filter is described herein. The bandpass filter has two parallel signal branches, each connected, on an input side, to an input node and, on an output side, to an output node. The two signal branches form a ring resonator, having a wave mode with a complex amplitude of {right arrow over (U)}CW=|{right arrow over (U)}CW|exp{?j?CW} propagating in a clockwise direction and a wave mode with a complex amplitude of {right arrow over (U)}CCW=|{right arrow over (U)}CCW|exp{?j?CCW} propagating in a counterclockwise direction. The vector sum of a resulting wave {right arrow over (U)}out at the output node of the bandpass filter at two or more stop frequencies is: {right arrow over (U)}out={right arrow over (U)}CW+{right arrow over (U)}CCW=0, and |{right arrow over (U)}CW|=|{right arrow over (U)}CCW| and |?CW??CCW|=180°. The stop frequencies are arranged such that a passband is formed between two stop frequencies.

Abstract: A ceramic multilayer construction includes three resonators designed as parallel strip lines that are capacitatively or magnetically coupled to each other. All circuit components are implemented in the form of metallizations in multilayer construction. Capacitative couplings are implemented by coupling capacitors. The strip line resonators are shortened by shunt arms to ground having grounding capacitors arranged therein.

Abstract: A bandpass filter is described herein. The bandpass filter has two parallel signal branches, each connected, on an input side, to an input node and, on an output side, to an output node. The two signal branches form a ring resonator, having a wave mode with a complex amplitude of ?CW=|?|exp{?j?CW} propagating in a clockwise direction and a wave mode with a complex amplitude of ?CCW=|?CCW|exp{?j?CCW} propagating in a counterclockwise direction. The vector sum of a resulting wave ?out at the output node of the bandpass filter at two or more stop frequencies is: ?out=?CW+?CCW=0, and |?CW|=|UCCW| and |?CW??CCW|=180°. The stop frequencies are arranged such that a passband is formed between two stop frequencies.

Abstract: A multiband circuit includes a signal path comprising a first signal branch that includes a first circuit that is transmissive in a first frequency band and a second signal branch that includes a second circuit that is transmissive in a second frequency band. The first and second signal branches are combined on an antenna side into a common path.