247 results about "Acoustic filters" patented technology

A method of optimizing the audio performance of an earpiece and the resultant device are provided. The disclosed earpiece combines at least two drivers within a single earpiece. If a pair of drivers is used, each driver has a discrete sound delivery tube. If more than two drivers are used, preferably the outputs from the two lower frequency drivers are merged into a single sound delivery tube while the output from the third driver is maintained in a separate, discrete sound tube. To compensate for the inherent phase shift of the earpiece the lengths of the sound delivery tubes, and thus driver offset, are regulated. Further audio performance optimization can be achieved through an iterative process of measuring the performance of the earpiece and making further, minor adjustments to the sound delivery tube lengths. The sound delivery tubes can include transition regions. The earpiece is configured to use removable / replaceable eartips. Acoustic filters can be interposed between one or both driver outputs and the earpiece output.

Disclosed are a film bulk acoustic resonator, a duplexer filter having the same, and a semiconductor package thereof. The film bulk acoustic resonator comprising: a semiconductor substrate; a lower electrode more than two layers formed at an upper surface of the semiconductor substrate; a piezoelectric layer deposited on an upper surface of the lower electrode with a certain thickness; and an upper electrode more than two layers formed at an upper surface of the piezoelectric layer, has an excellent bonding characteristic. The duplexer filter can microminiaturize a size thereof by integrating a film bulk acoustic filter formed by connecting the plurality of film bulk acoustic resonators serially and in parallel and peripheral passive elements of the film bulk acoustic filter into one semiconductor chip. Also, the semiconductor package is suitable for the duplexer filter.

An acoustic filter comprises a piezoelectric layer, an acoustic resonator structure monolithically disposed on the piezoelectric layer, a lumped capacitive structure monolithically disposed on the piezoelectric layer and being electrically coupled to the acoustic resonator structure. The acoustic resonator structure comprises an arrangement of planar interdigitated resonator fingers, and each of the interdigitated capacitive fingers has an edge that is entirely continuous. No portion of the edge of each of the interdigitated capacitive fingers is parallel to any portions of edges of the interdigitated resonator fingers. Each of the interdigitated capacitive fingers may comprise a plurality of interdigitated capacitive sub-fingers, or each of the interdigitated capacitive fingers may have a length / width ratio of less than two.

A method of optimizing the audio performance of an earpiece and the resultant device are provided. The disclosed earpiece combines at least two drivers within a single earpiece. If a pair of drivers is used, each driver has a discrete sound delivery tube. If more than two drivers are used, preferably the outputs from the two lower frequency drivers are merged into a single sound delivery tube while the output from the third driver is maintained in a separate, discrete sound tube. To compensate for the inherent phase shift of the earpiece the lengths of the sound delivery tubes, and thus driver offset, are regulated. Further audio performance optimization can be achieved through an iterative process of measuring the performance of the earpiece and making further, minor adjustments to the sound delivery tube lengths. The sound delivery tubes can include transition regions. The earpiece is configured to use removable / replaceable eartips. Acoustic filters can be interposed between one or both driver outputs and the earpiece output.

A MEMS acoustic filter has a MEMS resonator and at least two acoustic I / O ports to alter an input acoustic signal to an output acoustic signal. The first I / O port is adapted for interfacing with a medium, and the second I / O port for passing an acoustic signal to an acoustic transducer. Multiple MEMS resonators may be stacked to form a high order acoustic filter. An array of MEMS acoustic filters may be designed to function as an acoustic lens. The MEMS acoustic filter is particularly useful with an ultrasonic transducer, such as PZT and MUT. Fabrication methods to make the same are also disclosed.

An acoustic filter includes a signal input port, a ladder-type filter, a first branch ladder-type filter, a second branch ladder-type filter, and a signal output port. The first branch ladder-type filter and the second branch ladder-type filter are connected in parallel to each other. The signal input port is connected to the ladder-type filter. The ladder-type filter circuit is connected in series to the first branch ladder-type filter and the second branch ladder-type filter. The first branch ladder-type filter circuit and the second branch ladder-type filter are connected to the signal output port.

A multi-driver in-ear monitor for use with either a recorded or a live audio source is provided. If a pair of drivers is used, each driver has an individual sound delivery tube. If three drivers are used, the outputs from two of the drivers are merged into a single sound delivery tube while the output from the third driver is maintained in a separate, discrete sound tube. The sound delivery tubes remain separate throughout the end portion of the earpiece. The earpiece tip is configured to be fitted with any of a variety of sleeves (e.g., foam sleeves, flanged sleeves, etc.), thus allowing the in-ear monitor to be easily tailored to comfortably fit within any of a variety of ear canals. Due to the size constraints of such an earpiece, the sound delivery tubes include a transition region. Acoustic filters (i.e., dampers) can be interposed between one or both driver outputs and the earpiece output.

A surface mud pipeline system is described with a mechanical acoustic filter (1245) tuned to a predetermined frequency band so as to attenuate pump noise (132) within this band. The filter can be combined with a Venturi constriction to provide enhanced attenuation and is used to improve signal transmission of a mud pulse telemetry system (113-2).

A device and method for controlling the flow of a gaseous fuel from a fuel supply to a pressurized combustion chamber. A fuel pump is included in the gas train from supply to chamber. The fuel pump increases the pressure of the gas to allow efficient injection into the chamber. The pump is modulated to control the fuel flow. Both alternating current and pulse-width-modulated direct current signals may be used to control the flow. The pump may be a piston pump or a diaphragm pump. Feedback may be provided from sensors that determine operating parameters of the engine and such sensor signals may be used by the controller to maintain a parameter, such as temperature, at a specified value. An acoustic filter can be included in the gas train to significantly reduce gas flow pulsations generated by the pump. This filter improves the uniformity of the combustion process.

A multi-driver in-ear monitor for use with either a recorded or a live audio source is provided. If a pair of drivers is used, each driver has an individual sound delivery tube. If three drivers are used, the outputs from two of the drivers are merged into a single sound delivery tube while the output from the third driver is maintained in a separate, discrete sound tube. The sound delivery tubes remain separate throughout the end portion of the earpiece. The earpiece tip is configured to be fitted with any of a variety of sleeves (e.g., foam sleeves, flanged sleeves, etc.), thus allowing the in-ear monitor to be easily tailored to comfortably fit within any of a variety of ear canals. Due to the size constraints of such an earpiece, the sound delivery tubes include a transition region. Acoustic filters (i.e., dampers) can be interposed between one or both driver outputs and the earpiece output.

A micromachined capacitive acoustic transducer including an electrode formed by a perforated plate and another electrode formed by a shallowly corrugated membrane anchored at one or more positions on the substrate which also supports the said perforated plate is described. Also disclosed includes: a fixed perforated plate; a movable shallowly corrugated membrane having holes to form acoustic filter to a certain frequency or a range of frequencies spaced from the perforated plate that is anchored in one or more location but loose at other locations; a support structure in the perforated plate maintaining the minimum separation between the membrane and the perforated plate near the perimeter.

A method for collecting acoustic data from an industrial machine is disclosed. The method may include: providing an unmanned aerial vehicle (UAV) having an acoustic receiver attached thereto; and positioning the unmanned aerial vehicle at a specific location so that the acoustic receiver collects acoustic data from the industrial machine at the specific location. An acoustic receiver is attached to the UAV for collecting acoustic data from the industrial machine. An acoustic filter is attached to the acoustic receiver and the UAV for filtering unwanted sound from the acoustic data. Acoustic data can be used by a flight control system to identify a specific location relative to the industrial machine that is a source a specific acoustic signature emanating from the industrial machine.

Devices, systems, and methods manipulate target materials within fluids, and may be useful for removing microbubbles and other materials from blood. Ultrasound or acoustic filtering waves may be directed across a flow of blood, and differences in density between the target microbubbles and the blood may enhance separation by driving the lighter matter upward for removal from the blood stream. A disposable acoustically transmissive conduit can replaceably engage an ultrasound transmitter to facilitate sterilization. Exemplary conduits have elongate lumen cross-sections and an axial path resembling a portion of a Mobius strip.

An acoustic filter and method of acoustic filter manufacture provides a plurality of series acoustic resonators coupled in series on a first resonator substrate, a plurality of shunt resonators on a second resonator substrate, and a support substrate. The first and second resonator substrates are mounted on the support substrate. The filter further provides a plurality of electrical connections, wherein each respective electrical connection electrically couples a respective one of the plurality of shunt resonators to a respective one of the plurality of series acoustic resonators.

An acoustic transducer comprising: a mechanical acoustic filter configured to be electrically controllable to change the acoustic properties of the transducer.

A MEMS ultrasonic device has an array of PZT transducer elements and a cMUT structure bonded to the array of PZT transducer elements. The MEMS ultrasonic device can be adapted for ultrasonic imaging. The cMUT structure may serve as an active MEMS acoustic filter having at least two acoustic I / O ports to alter an input acoustic signal to an output acoustic signal. The first I / O port is adapted for interfacing with a medium, and the second I / O port for passing an acoustic signal to an acoustic transducer. An array of MEMS acoustic filters may be designed to function as an acoustic lens. Fabrication methods to make the same are also disclosed.

A semiconductor wafer is formed with a first device layer having active devices. A handle wafer having a trap rich layer is bonded to a top surface of the semiconductor wafer. A second device layer having a MEMS device or acoustic filter device is formed on a bottom surface of the semiconductor wafer. The second device layer is formed either by monolithic fabrication processes or layer-transfer processes.

A surface mud pipeline system is described with a mechanical acoustic filter (1245) tuned to a predetermined frequency band so as to attenuate pump noise (132) within this band. The filter can be combined with a Venturi constriction to provide enhanced attenuation and is used to improve signal transmission of a mud pulse telemetry system (113-2).

The invention relates to a high speed frequency sweep apparatus which comprises a data acquisition unit, a frequency selection filtering unit and a processing unit, wherein the data acquisition unit is used for acquiring a cellular network downlink signal, and after low noise amplification, the signal is sent to the frequency selection filtering unit; the frequency selection filtering unit is used for selecting different surface acoustic filters and carrying out selection of radio frequency bands under the control of the processing unit, and directly converting the signal which is subjected to radio frequency band selection into an analog baseband signal simultaneously; the processing unit controls the frequency selection filtering unit to select different surface acoustic filters and carry out the selection of the radio frequency bands, and demodulates the analog baseband signal. The invention provides the frequency sweep apparatus, high speed multichannel frequency sweep is realized, and the apparatus is suitable for communication networks of different standards.

There is disclosed active acoustic filter systems and methods. A processor is disposed within a housing configured to interface with a user's ear. A memory stores data defining one or more locations and a respective set of location-based processing parameters associated with each of the one or more locations. A personal computing device external to the housing is coupled to the processor via a first wireless communications link. The personal computing device determines a current location of the active acoustic filter system. The processor generates digitized processed sound by processing digitized ambient sound in accordance with a set of location-based processing parameters retrieved from the memory, the retrieved set of location-based processing parameters associated with the current location of the active acoustic filter system as determined by the personal computing device.

There are disclosed acoustic resonators and radio frequency filter devices. An acoustic resonator includes a piezoelectric plate having a front surface. A conductor pattern is formed on the front surface, the conductor pattern including interdigital transducers (IDTs) of one or more pairs of sub-resonators, each pair consisting of two sub-resonators. The two sub-resonators of each pair of sub-resonators are positioned symmetrically about a central axis.

A film bulk acoustic wave filter assembly includes a film bulk acoustic filter and an RF circuit. The film bulk acoustic filter unit cell includes a plurality of film bulk acoustic wave resonators. The number, area and arrangement of the resonators depend on the characteristics of the filter. In the film bulk acoustic wave filter, a metal layer made by CMOS processes is used as a lower electrode area of the film bulk acoustic wave filter or a suspended chamber. The film bulk acoustic filter can be integrated with the RF circuit using processes such as the CMOS process. It facilitates the integration of active devices, streamlining of system design and simplification of test processes, and has a great influence on the application of RF communication devices and integration of system-system-chip (SOC).

A pressure transducer for measuring pressures in high temperature environments employs a tube which is terminated at one end by an acoustic micro-filter. The acoustic filter or micro-filter has a plurality of apertures extending from one end to the other end, each aperture is of a small diameter as compared to the diameter of the transducer and the damper operates to absorb acoustic waves impinging on it with limited or no reflection. Mounted to the tube is a pressure transducer with a diaphragm flush with the inner wall of the tube. The tube is mounted in an aperture in a casing of a gas turbine operating at a high temperature. The hot gases propagate through the tube where the pressure of the gases are measured by the transducer coupled to the tube and where the acoustic filter operates to absorb acoustic waves impinging on it with little or no reflection, therefore enabling the pressure transducer to be mainly responsive to high frequency waves associated with the gas turbine operation.

A device and method for controlling the flow of a gaseous fuel from a fuel supply to a pressurized combustion chamber. A fuel pump is included in the gas train from supply to chamber. The fuel pump increases the pressure of the gas to allow efficient injection into the chamber. The pump is modulated to control the fuel flow. Both alternating current and pulse-width-modulated direct current signals may be used to control the flow. The pump may be a piston pump or a diaphragm pump. Feedback may be provided from sensors that determine operating parameters of the engine and such sensor signals may be used by the controller to maintain a parameter, such as temperature, at a specified value. An acoustic filter can be included in the gas train to significantly reduce gas flow pulsations generated by the pump. This filter improves the uniformity of the combustion process.

The invention relates to a grooved surface acoustic filter chip packaging structure and a manufacturing method thereof. The structure comprises a surface acoustic filter chip wafer (1), and the surface of the surface acoustic filter chip wafer (1) includes electrode areas (1.1) and an induction area (1.2). A first metal layer (2) is arranged on the surface of each electrode area (1.1). A laminated wafer (4) is arranged above the surface acoustic filter chip wafer (1). A cavity (7) is formed between the laminated wafer (4) and the induction area (1.2). The laminated wafer (4) is provided with holes (8) at the positions of the electrode areas (1.1), a metal ball (6) is arranged in each hole (8), and the metal balls (6) are in contact with the first metal layers (2) respectively. According to the grooved surface acoustic filter chip packaging structure and the manufacturing method thereof of the invention, a surface acoustic filter of smaller area and size and lower manufacturing cost can be provided.

A system for actively damping the low-frequency coloration of sound in a listening room is provided comprising an acoustic wave sensor, an acoustic wave actuator, and an electronic feedback controller. The listening room defines at least one mode of low-frequency coloration. The acoustic wave actuator is substantially collocated with the acoustic wave sensor within the listening room. The electronic feedback controller is operative to generate a signal at its output by applying a feedback controller transfer function. The feedback controller transfer function comprises a second order differential equation including a first variable representing a predetermined damping ratio and a second variable representing a tuned natural frequency and creates a 90 degree phase lead substantially at the resonant frequencies of at least one mode of low-frequency coloration. The feedback controller output signal represents a rate of change of volume velocity to be produced by the acoustic wave actuator. Further provided are methods for actively damping the low-frequency coloration of sound within a listening room and systems for actively treating noise within a fluid-carrying duct, including those which employ active low- and high-pass acoustic filters.

An acoustic filter is provided with a single flow chamber for exposure of a flexible rubber layer to liquid undergoing flow through the flow chamber with noise producing acoustic energy therein. The flexible rubber layer is supported on a cylindrical drum with slanted holes therein through which the exposure to the liquid in the flow chamber is effected. An axially sectioned drum with dimensionally different diameters, radial thicknesses and slanted holes therein is positioned over the rubber layer within an outer casing to establish a plurality of gas-filled cavities of different axial lengths and separated from each other along the axial length of the liquid flow chamber which is connected at its opposite axial ends by pipe sections to a piping system from which the liquid within the flow chamber is derived.

It is an objective of the present invention to provide a pressure transducer assembly for measuring pressures in high temperature environments that employs an elongated tube which is terminated at one end by an acoustic micro-filter. The micro-filter has a plurality of apertures extending from one end to the other end, each aperture is of a small diameter as compared to the diameter of the transducer and the damper operates to absorb acoustic waves impinging on it with limited or no reflection. To improve the absorption of acoustic waves, the elongated tube may be tapered and / or mounted to a support block and further convoluted to reduce the overall size and mass of the device. A pressure transducer with a diaphragm flush may be mounted to the elongated tube and extend through to the inner wall of the tube. Hot gases propagate through the elongated tube and their corresponding pressures are measured by the transducer. The acoustic filter operates to absorb acoustic waves resultant from the hot gases, therefore enabling the pressure transducer to be mainly responsive to high frequency waves associated with the gas turbine operation.