Abstract: A surface acoustic wave device includes a piezoelectric substrate made of ?° rotated Y-cut X-propagation LiNbO3 having a cut angle ?, an IDT electrode on the piezoelectric substrate and including a plurality of electrode fingers, and a dielectric film on the piezoelectric substrate and covering the IDT electrode. The IDT electrode includes a main electrode layer and an auxiliary conductive layer. The main electrode layer is, compared to the auxiliary conductive layer, closer to a side of the piezoelectric substrate. The main electrode layer includes Pt as a main component. Where the film thickness of the main electrode layer is denoted as h, the film thickness of the dielectric film is denoted as H, and a wavelength determined by the electrode finger pitch of the IDT electrode is denoted as ?, the relationship in Formula (1) and Equation (2A) to Equation (2D) is satisfied.

Abstract: An acoustic wave device comprises a piezoelectric substrate, interdigital transducer electrodes having an electrode pitch ?0, and first and second reflector gratings disposed on opposite respective sides of the interdigital transducer electrodes in a propagation direction of a main acoustic wave through the acoustic wave device, the first reflector grating having a reflector electrode pitch ?1 throughout an entirety of the first reflector grating that is different than a reflector electrode pitch ?2 throughout an entirety of the second reflector grating to suppress ripples in a conductance curve of the acoustic wave device.

Abstract: An acoustic wave device includes a support substrate, a piezoelectric body including LiTaO3, a first electrode on a first main surface of the piezoelectric body, a second electrode on a second main surface, an acoustic-layer laminated body between a support substrate and the piezoelectric body. The azimuth angle of the piezoelectric body is (about 85° to 95°, about 85° to 95°, about 5° to 65°) represented in Euler angles.

Abstract: An acoustic wave device comprises a substrate including a piezoelectric material, interdigital transducer (IDT) electrodes disposed on a surface of the substrate, a first dielectric film having a lower surface disposed on the IDT electrodes and the surface of the substrate, first strips formed of a first material having a density greater than a density of the first dielectric film disposed within the first dielectric film over tips of the interdigitated electrode fingers in the edge regions of the IDT electrodes, and second strips formed of a second material having a density greater than the density of the first dielectric film disposed within the first dielectric film in the gap regions of the IDT electrodes, laterally spaced from the first strips in a direction perpendicular to a direction of propagation of a main acoustic wave through the acoustic wave device, and extending only partially over the gap regions.

Abstract: Filters and methods of making filters are disclosed. A filter device includes a substrate, a piezoelectric plate, and an acoustic Bragg reflector between a surface of the substrate and a back surface of the piezoelectric plate. A conductor pattern on a front surface of the piezoelectric plate includes interdigital transducers (IDTs) of a plurality of resonators and a plurality of conductors to connect the plurality of resonators in a ladder filter circuit, the plurality of conductors including adjacent first and second conductors. A portion of the piezoelectric plate between the first and second conductors is removed.

Abstract: An acoustic resonator device includes a conductor pattern formed on a surface of a piezoelectric plate. The conductor pattern includes a first busbar, a second busbar, and n interleaved parallel fingers of an interdigital transducer (IDT), where n is a positive integer. The fingers extend alternately from the first and second busbars. A first finger and an n'th finger are at opposing ends of the IDT. The conductor pattern also includes a first reflector element proximate and parallel to the first finger and a second reflector element proximate and parallel to the n'th finger. A center-to-center distance pr between the first reflector element and the first finger and between the second reflector element and the n'th finger is greater than or equal to 1.2 times a pitch p of the IDT and less than or equal to 1.5 times the pitch p.

Abstract: A ladder-type filter includes a support substrate, a piezoelectric layer provided on the support substrate, a parallel resonator including first electrode fingers provided on the piezoelectric layer and having a first average pitch and a first average duty ratio, a largest first average pitch being equal to or greater than two times a thickness of the piezoelectric layer, a first end of the parallel resonator being coupled to a path between input and output terminals, a second end of the parallel resonator being coupled to a ground, and a series resonator connected in series between the input and output terminals, the series resonator including second electrode fingers provided on the piezoelectric layer and having a second average pitch and a second average duty ratio, a second average duty ratio in at least one series resonator being less than a smallest first average duty ratio.

Abstract: An acoustic wave filter includes acoustic wave resonators including a piezoelectric substrate and an IDT electrode including first and second electrode fingers. An intersecting region of the first and second electrode fingers includes a central region and first and second edge regions on outer side portions of the central region. An acoustic velocity in the first and second edge regions is lower than that in the central region, and the acoustic wave resonators include a first acoustic wave resonator with a width in the first and second edge regions larger than a width in the central region, and a second acoustic wave resonator including at least one of an acoustic velocity reducing film and an acoustic velocity increasing film in the central region, such that an acoustic velocity in the first and second edge regions is lower than acoustic velocity in the center region.

Abstract: Aspects of this disclosure relate to a multiplexer with an acoustic assisted trap circuit. The multiplexer includes an acoustic wave filter with an acoustic wave resonator and an impedance network that together provide a trap for a harmonic associated with another acoustic wave filter of the multiplexer. The acoustic wave filter can have an edge of a passband that is farther from the harmonic than other acoustic filters of the multiplexer.

Abstract: A surface acoustic wave resonator that has at least a first resonant frequency and a second resonant frequency is disclosed. The surface acoustic wave resonator can include an interdigital transducer electrode that is positioned over a piezoelectric layer. The interdigital transducer electrode includes fingers having a first pitch. The surface acoustic wave resonator can also include a first set of reflectors that is positioned over the piezoelectric layer. The first set of reflectors includes a first number of reflectors having a second pitch. The first pitch is greater than the second pitch. The surface acoustic wave resonator can also include a second set of reflectors that is positioned over the piezoelectric layer. The second set of reflectors includes a second number of reflectors having a third pitch. The second number of reflectors is different from the first number of reflectors.

Abstract: An electro acoustic resonator is provided. The resonator has a gap short structure (GSS) to electrically short at least an area of the transversal gap to suppress transversal gap mode excitations. The gap short structure may be provided by a conductive stripe in the gap and parallel to or inclined with respect to the bus bar (BB) shorting adjacent IDT fingers. Additional connectors between the stripe and the bus bar may be provided. The connectors may have different pitch or metallization ratio with respect to the ID fingers. The connectors may be offset from the position of the fingers and my be inclined with respect to the bus bars. Multiple parallel stripes in the gap may provide a transversal reflector. By using a gap short structure a further improved transversal mode suppression of piston mode designs can be achieved.

Abstract: Interdigital transducer (IDT) and reflective structure arrangements for surface acoustic wave (SAW) devices are disclosed. Representative SAW devices are described herein with reduced overall size while maintaining good quality factors. In certain embodiments, a SAW device may include an IDT arranged between reflective structures on a piezoelectric material. The reflective structures may include reflective IDTs that are configured to have a phase difference with the IDT to reflect and confine acoustic waves in the piezoelectric material. In certain embodiments, the reflective structures may be electrically connected to at least one of an input signal or an output signal. In this manner, the reflective structures may be configured with reduced size as compared to conventional reflective structures such as gratings, thereby providing a SAW device with reduced dimensions without a negative impact on device performance.

Abstract: A filter includes first and second input/output terminals; an LC parallel resonance circuit that includes an inductor L1 and a capacitor C1 connected to each other in parallel; and an acoustic wave series resonance circuit that includes series arm resonators s1 and s2 connected to each other in series. The LC parallel resonance circuit and the acoustic wave series resonance circuit are connected to each other in series between the first input/output terminal and the second input/output terminal.

Abstract: A surface acoustic wave resonator, a filter, a manufacturing method thereof and a communication device. The surface acoustic wave resonator includes a piezoelectric material layer, an interdigital transducer and a dielectric layer; the interdigital transducer is located at a side of the piezoelectric material layer, and the dielectric layer is located between the interdigital transducer and the piezoelectric material layer. Therefore, the surface acoustic wave resonator can reduce the electromechanical coupling coefficient of the surface acoustic wave resonator by arranging the dielectric layer between the interdigital transducer and the piezoelectric material layer. In addition, the surface acoustic wave resonator can adjust the electromechanical coupling coefficient of the surface acoustic wave resonator by controlling the thickness of the dielectric layer.

Abstract: An acoustic wave element includes an electrode-finger pitch of reflecting-electrode fingers greater than an electrode-finger pitch pi of comb-shaped electrode fingers, and a center-to-center distance between a reflecting-electrode finger and a comb-shaped electrode finger is equal to or less than about 0.9 times the electrode-finger pitch of the reflecting-electrode fingers.

Abstract: Acoustic filters are disclosed. A substrate includes a base and an intermediate layer. A piezoelectric plate is attached to the intermediate layer, portions of the piezoelectric plate forming one or more diaphragms spanning respective cavities in the intermediate layer. A conductor pattern on a front surface of the piezoelectric plate includes interdigital transducers (IDTs) of a plurality of resonators, interleaved fingers of each of the IDTs disposed on a respective diaphragm of the one or more diaphragms. A first frequency setting dielectric layer having a first thickness is disposed over the fingers of the IDTs of a first subset of the plurality of resonators. A second frequency setting dielectric layer having a second thickness greater than the first thickness is disposed over the fingers of the IDTs of a second subset of the plurality of resonators, wherein the first subset and the second subset are not identical.

Abstract: To provide a radio-frequency module and a communication apparatus that are capable of suppressing degradation in filter characteristics while reducing the sizes of the radio-frequency module and the communication apparatus. A radio-frequency module (1) includes a common terminal, a first filter (21), a second filter (22), a mounting substrate (3), and an external connection terminal (8a). The first filter (21) is connected to the common terminal and transmits a first signal in a first frequency band. The second filter (22) is connected to the common terminal and transmits a second signal in a second frequency band. The mounting substrate (3) has the first filter (21) mounted thereon. The first filter (21) is connected to the mounting substrate (3) with the external connection terminal (8a). The second filter (22) is laminated on the first filter (21). The external connection terminal (8a) is the common terminal.

Abstract: Electroacoustic device (5) comprising: —an ultrasonic wave transducer (15) comprising a piezoelectric substrate (10) and first (30) and second (35) electrodes in contact with the piezoelectric substrate, and —a carrier (10), the transducer being attached to the carrier and acoustically coupled to the carrier, and the first and second electrodes being sandwiched, at least partly, between the piezoelectric substrate and the carrier, the device being configured to generate an ultrasonic surface wave (W) propagating through the carrier at a distance from the transducer when an electric current passes through the first and second electrodes.

Abstract: Surface acoustic wave (SAW) structures with transverse mode suppression are disclosed. In one aspect, the SAW structure provides digits or fingers with broad interior terminal end shapes. By providing such shapes spurious modes above the resonance frequency of the SAW are suppressed thereby providing desired out of band rejection that helps satisfy design criteria such as keeping a higher Q value, a higher K2 value and better Temperature Coefficient of Frequency (TCF).

Abstract: A filter device includes a first substrate, a first input electrode and a first output electrode on the first substrate, a first ground electrode on the first substrate and receiving a ground potential, an electrically open portion in or on the first substrate, a second substrate mounted on the first substrate, a second input electrode on a surface of the second substrate and connected to the first input electrode, a second output electrode on the surface of the second substrate and connected to the first output electrode, a second ground electrode on the surface of the second substrate and connected to the first ground electrode, and at least one first functional electrode on the second substrate and disposed on a first connecting path connecting the second input electrode and the second output electrode. The open portion is connected to the first connecting path.

Abstract: A signal transmission circuit includes a common frequency filter configured to filter a signal centering on a common frequency that is an anti-resonance frequency; a first frequency filter configured to filter a signal centering on a first frequency that is an anti-resonance frequency; a second frequency filter configured to filter a signal centering on a second frequency that is an anti-resonance frequency; a first route connected to a first signal wiring line configured to transmit a digital signal; and a second route connected to a second signal wiring line configured to transmit a digital signal.

Abstract: A filter integrated circuit, including an acoustic wave filter chip and a matching circuit, is provided. The acoustic wave filter chip is covered upon a substrate. The matching circuit is disposed on the substrate to provide matching impedance to the acoustic wave filter chip. A first pad and a second pad of the matching circuit are respectively connected to a first signal terminal and a second signal terminal of the acoustic wave filter chip. First terminals of a first coil inductor and a second coil inductor of the matching circuit are respectively connected to the first pad and the second pad of the substrate. The first coil inductor is adjacent to the second coil inductor, so that mutual inductance and parasitic capacitance are formed, so that the matching circuit and the acoustic wave filter chip jointly generate a transmission zero point located in a triple fundamental frequency range.

Abstract: An acoustic wave filter includes a longitudinally coupled resonator including IDT electrodes and a reflector. A standard deviation of a pitch deviation rate of at least one of the reflector and the IDT electrodes is greater than or equal to about 1.4%.

Abstract: A wafer-level package for micro-acoustic devices and a method of manufacture is provided. The package comprises a base wafer with electric device structures. A frame structure is sitting on top of the base wafer enclosing particular device areas for the micro-acoustic devices. A cap wafer provided with a thin polymer coating is bonded to the frame structure to form a closed cavity over each device area and to enclose within the cavity the device structures arranged on the respective device area.

Abstract: A surface acoustic wave device is disclosed. The surface acoustic wave device can include a ceramic substrate, a piezoelectric layer over the ceramic substrate, and an interdigital transducer electrode over the piezoelectric layer. The ceramic substrate can be a polycrystalline spinel substrate. The surface acoustic wave device can also include a temperature compensating layer over the interdigital transducer electrode.

Abstract: A SAW transducer and a SAW resonator are proposed composed of consecutively arranged unit cells of length L. Slight geometry or material variations such as variations of the metallization ration or the unit cell length L affecting the pitch) between these unit cells result in improved spurious mode suppression while the main mode performance is unaffected.

Abstract: A first filter of a multiplexer includes serial resonators and parallel resonators that are acoustic wave resonators. A first of the serial resonators that is closer to a common terminal than the other serial resonators is connected to the common terminal without the parallel resonators interposed therebetween. Each of the elastic wave resonators includes a substrate having piezoelectricity, an IDT electrode provided on the substrate, and a dielectric layer provided on the substrate to cover the IDT electrode. A thickness of the dielectric layer of the first serial resonator is smaller than a thickness of each of the dielectric layers of the remainder of the elastic wave resonators.

Abstract: An acoustic wave device includes a piezoelectric substrate, and an IDT electrode on the piezoelectric substrate. The piezoelectric substrate includes a high acoustic velocity layer, and a piezoelectric layer. The IDT electrode includes a first busbar and a second busbar, and first and second electrode fingers interdigitated with each other. A first envelope and a second envelope each extend in a slanted direction with respect to an acoustic wave propagation direction, the first envelope being an imaginary line formed by connecting tips of the first electrode fingers, the second envelope being an imaginary line formed by connecting tips of the second electrode fingers. The first dielectric film is located in at least one gap of first and second gaps, the first gaps being located between the first electrode fingers and the second busbar, the second gaps being located between the second electrode fingers and the first busbar. The first dielectric film has a density greater than a density of silicon oxide.

Abstract: A resonator includes: interdigital transducer (IDT) including first electrode including first base on piezoelectric substrate and extended in reference direction, and first protrusions connected to the first base and extended in direction intersecting with the reference direction, and second electrode including second base on the piezoelectric substrate and extended in the reference direction, and second protrusions connected to the second base and extended in direction intersecting with the reference direction, each of the second protrusions extended to have one of the first protrusions inserted between the second protrusion and another second protrusion adjacent to the second protrusion, wherein a width of each of first specific protrusions included between one end of the IDT and first position at first distance from the one end, among the first protrusions and the second protrusions, decreases from first specific protrusion closest to the first position toward first specific protrusion closest to the one e

Abstract: A double mode SAW (DMS) filter includes: a plurality of interdigital transducers (IDTs), each having a plurality of Type 1 electrode fingers and a plurality of Type 2 electrode fingers formed on a piezoelectric substrate, wherein one Type 2 electrode finger among the plurality of Type 2 electrode fingers is disposed between two adjacent Type 1 electrode fingers among the plurality of Type 1 electrode fingers, and in a first IDT and a second IDT included in the plurality of IDTs to be adjacent to each other, one Type 1 electrode finger of the second IDT is disposed between two Type 1 electrode fingers of the first IDT. Accordingly, it is possible to provide a DMS filter capable of improving the amount of attenuation in an attenuation band adjacent to the wide band side for the passband and miniaturizing a product by saving space.

Abstract: An acoustic wave device includes a substrate, an interdigital transducer electrode including electrode fingers on a main surface of the substrate, and a protection film covering the main surface of the substrate, and side surfaces and upper surfaces of the electrode fingers. The protection film includes a portion covering the main surface of the substrate, an intermediate portion between two of the electrode fingers adjacent to each other, and a vicinity portion of the electrode fingers. The intermediate portion is thicker than the vicinity portion.

Abstract: An acoustic wave filter device includes first and second terminals, an inductor connected to the first terminal, and a longitudinally coupled resonator coupled between the inductor and the second terminal. The longitudinally coupled resonator includes at least one first IDT electrode coupled to the first terminal, and at least one second IDT electrode connected to the second terminal. A total capacitance value of the at least one first IDT electrode is greater than a total capacitance value of the at least one second IDT electrode.

Abstract: A filter device has a first piezoelectric plate spanning a first and second cavity of a substrate. A first and second interdigital transducer (IDT) are on a front surface of the first piezoelectric plate over the first and second cavity. A dielectric layer is formed on the first piezoelectric plate and covers the first IDT and second IDT. A second piezoelectric plate is bonded to a front surface of the dielectric layer over the first cavity and the second cavity. A second dielectric layer is formed on a front surface of the second piezoelectric plate over the first cavity but not over the second cavity. The thickness of the dielectric layer, the first piezoelectric plate and the second piezoelectric plate can be selected to tune a shunt resonator over the first cavity and a series resonator over the second cavity.

Abstract: An acoustic wave device comprises a piezoelectric substrate, interdigital transducer electrodes having an electrode pitch ?0, and first and second reflector gratings disposed on opposite respective sides of the interdigital transducer electrodes in a propagation direction of a main acoustic wave through the acoustic wave device, the first reflector grating having a different electrode pitch ?1 than an electrode pitch ?2 of the second reflector grating to suppress ripples in a conductance curve of the acoustic wave device.

Abstract: A multiplexer includes a plurality of filters, in which one input/output terminal of each of the plurality of filters is connected to a common terminal, a first filter included in the plurality of filters is a ladder filter and includes at least one series arm resonator connected on a path connecting the common terminal and another input/output terminal of the first filter, at least one parallel arm resonator connected between a connection node provided on the path and a ground, and a switch which is connected in series to a parallel arm resonator connected most nearby to the common terminal among at least one parallel arm resonator and switches between conduction and non-conduction of a node to which the parallel arm resonator is connected and the ground.

Abstract: Aspects of this disclosure relate to a surface acoustic wave device with a vertical stack over a piezoelectric layer. The vertical stack can include a first acoustic reflector disposed on the piezoelectric layer, a second acoustic reflector disposed on the piezoelectric layer, and an interdigital transducer electrode disposed on the piezoelectric layer and positioned between the first acoustic reflector and the second acoustic reflector. The interdigital transducer electrode has a first side that is closer to the first acoustic reflector and a second side that is closer to the second acoustic reflector. A vertical arrangement of the vertical stack can be configured such that an acoustic wave propagation velocity of a first region between the first side and a first reflector is faster than an acoustic wave propagation velocity of a second region between the first side and the second side.

Abstract: An acoustic wave filter device includes first and second terminals, a longitudinally coupled resonator coupled between the first terminal and the second terminal, and an inductor connected between a path and a ground potential, the path connecting the first terminal and the longitudinally coupled resonator to each other. The longitudinally coupled resonator includes at least one first IDT electrode coupled to the first terminal, and at least one second IDT electrode connected to the second terminal. A total capacitance value of the at least one first IDT electrode is smaller than a total capacitance value of the at least one second IDT electrode.

Abstract: An acoustic wave filter includes a series-arm resonator, a first parallel-arm resonator, and a second parallel-arm resonator. The series-arm resonator is disposed on a path connecting first and second input/output terminals. The first parallel-arm resonator is disposed on a path that connects ground with a node, which is located on a path connecting the series-arm resonator with the first input/output terminal. The second parallel-arm resonator is disposed on a path that connects ground with a node, which is located on a path connecting the series-arm resonator with the second input/output terminal. The parallel-arm resonator has a resonant frequency lower than the resonant frequency of the second parallel-arm resonator. The first parallel-arm resonator has an anti-resonant frequency higher than the anti-resonant frequency of the second parallel-arm resonator. The second parallel-arm resonator has the highest resonant frequency of all the parallel-arm resonators.

Abstract: An acoustic wave device includes first and second acoustic wave elements. The first acoustic wave element is disposed on a piezoelectric substrate, and includes at least one first IDT electrode. The second acoustic wave element is disposed on the piezoelectric substrate, and includes at least one second IDT electrode. The first and second acoustic wave elements are adjacent to each other in the direction of acoustic wave propagation. A diffracting component that diffracts an acoustic wave is disposed between the first IDT electrode and the second IDT electrode. The diffracting component includes a gap that defines and functions as a slit to diffract an acoustic wave.

Abstract: A radio frequency filter includes at least a first sub-filter and a second sub-filter connected in parallel between a first port and a second port. Each of the sub-filters has a piezoelectric plate having front and back surfaces, the back surface attached to a substrate, and portions of the piezoelectric plate forming diaphragms spanning respective cavities in the substrate. A conductor pattern is formed on the front surface of the plate, the conductor pattern includes interdigital transducers (IDTs) of a respective plurality of resonators, with interleaved fingers of each IDT disposed on a respective diaphragm of the plurality of diaphragms. A thickness of the portions of the piezoelectric plate of the first sub-filter is different from a thickness of the portions of the piezoelectric plate of the second sub-filter.

Abstract: An elastic wave device includes an LiNbO3 substrate, a first elastic wave resonator including a first IDT electrode and a first dielectric film, and a second elastic wave resonator including a second IDT electrode and a second dielectric film. A Rayleigh wave travels along at least one surface of the elastic wave device. A thickness of the first dielectric film differs from a thickness of the second dielectric film. A propagation direction of an elastic wave in the first elastic wave resonator coincides with a propagation direction of an elastic wave in the second elastic wave resonator. Euler angles of the LiNbO3 substrate fall within a range of (0°±5°, ?, 0°±10°).

Abstract: A filter includes an additional circuit including first and second IDT electrode groups connected in multiple stages between first and second input/output terminals, the first IDT electrode group includes first and second IDT electrodes side by side in a propagation direction of an acoustic wave, and the second IDT electrode group includes third and fourth IDT electrodes side by side in the propagation direction. One end of each of the first and second IDT electrodes is respectively connected to the first and second input/output terminals. Other ends of the first and second IDT electrodes are connected in common and to a ground. One ends of the third and fourth IDT electrodes are connected in common. Other ends of the third and fourth IDT electrodes are connected in common. The additional circuit is connected in parallel with at least a portion of a filter circuit.

Abstract: A BAW resonator filter can include a BAW resonator pass-band filter ladder, the BAW resonator pass-band filter ladder can be configured to pass frequency components of an input signal in a pass-band of frequencies received at an input node of the BAW resonator pass-band filter ladder to an output node of the BAW resonator pass-band filter ladder. A first rejection-band series resonator can be coupled in series between an input port of the BAW resonator pass-band filter ladder and the input node, the first rejection-band series resonator can have a first anti-resonant frequency peak in a rejection-band of frequencies that is less than the pass-band of frequencies. A second rejection-band series resonator can be coupled in series between an output port of the BAW resonator filter and the output node, the second rejection-band series resonator can have a second anti-resonant frequency peak in the rejection-band of frequencies.

Abstract: Aspects of this disclosure relate to a multiplexer that includes an acoustic wave filter including acoustic wave resonators on at least two die with a transmission line electrically connecting the acoustic wave resonators on the two die. The acoustic wave filter can include a plurality of acoustic wave resonators on a first die electrically connected to at least one acoustic wave resonator on a second die via the transmission line. The acoustic wave resonator on the second die can provide a relatively high impedance at a respective passband of one or more other filters of the multiplexer. This can reduce effects of the transmission line of the acoustic wave filter on a respective passband of one or more other filters of the multiplexer.

Abstract: An acoustic wave device includes a piezoelectric substrate including a piezoelectric layer made of lithium tantalate, an IDT electrode on the piezoelectric substrate, and a pair of reflectors on both sides of the IDT electrode on the piezoelectric substrate in an acoustic wave propagation direction. SH waves are used as a principal mode. The IDT electrode includes electrode fingers and the pair of reflectors each including electrode fingers. When a length along a direction orthogonal to a direction in which the electrode fingers extend is a width, each of the reflectors includes first and second electrode fingers having different widths. Four consecutive electrode fingers, which are any four of the electrode fingers of each of the reflectors, include both of the first and second electrode fingers and distances between centers of the four consecutive electrode fingers are equal or substantially equal.

Abstract: Aspects of the disclosure relate to wireless communication, and high-frequency filters with resonators configured to systematically modify phase characteristics of an antenna reflection coefficient. One example is a wireless communication apparatus for a multi-band system comprising a frequency band filter circuit having a filter passband that includes a first band of the multi-band system. The frequency band filter circuit comprises a plurality of resonators coupled between an antenna port and a signal port and a resonant structure electrically coupled to the plurality of resonators. The resonant structure has a resonance outside of the first band and a second band of the multi-band system, the resonance being closer to the second band than to the first band.

Abstract: According to various embodiments, there is provided a resonator device that includes a first interdigital transducer and a second interdigital transducer that is electrically connected to the first interdigital transducer. Both the first interdigital transducer and the second interdigital transducer are configured to resonate at a common frequency. At least one of an electrode width and an electrode pitch of the first interdigital transducer is different from the respective electrode width and/or electrode pitch of the second interdigital transducer such that spurious peaks of the resonator device are lower in amplitude as compared to spurious peaks of each of the first interdigital transducer and the second interdigital transducer.

Abstract: Aspects of this disclosure relate to an acoustic wave device that includes a multi-layer interdigital transducer electrode. The acoustic wave device includes a piezoelectric layer and an interdigital transducer electrode on the piezoelectric layer. The interdigital transducer electrode includes a first interdigital transducer electrode layer positioned between a second interdigital transducer electrode layer and the piezoelectric layer. The second interdigital transducer electrode layer can include aluminum and having a thickness of at least 200 nanometers. The acoustic wave device can include a temperature compensation layer arranged such that the interdigital transducer electrode is positioned between the piezoelectric layer and at least a portion of the temperature compensation layer. Related filters, modules, wireless communication devices, and methods are disclosed.

Abstract: An acoustic wave device includes a supporting substrate, an acoustic reflection layer, a piezoelectric layer, and an IDT electrode. At least one of a high acoustic impedance layer and a low acoustic impedance layer is a conductive layer in the acoustic reflection layer. When a wavelength of an acoustic wave determined by an electrode finger pitch of the IDT electrode is ? and a region between an envelope of tips of first electrode fingers and an envelope of tips of second electrode fingers is an intersecting region, the conductive layer overlaps at least the intersecting region in plan view in a thickness direction of the supporting substrate, and a distance from the tips of the first electrode fingers to an end of the conductive layer in a direction in which the first electrode fingers extend is more than 0 and not more than about 12?.

Abstract: A radio frequency module includes a radio frequency filter (10), and the radio frequency filter (10) includes a terminal (11), a terminal (12), an impedance element (Z) disposed in series on a path (13) connecting the terminal (11) and the terminal (12), and a parallel arm resonator (P) connected between a node (N) on the path (13) and a ground. The impedance element (Z) is a capacitor or an inductor, and a wiring length A1 between the node (N) and the parallel arm resonator (P) is shorter than a wiring length B1 between the impedance element (Z) and a terminal (terminal (11), for example) out of the terminal (11) and the terminal (12) having a shorter wiring length to the impedance element (Z).