Abstract: Provided is a distance measurement system, including: at least one sound source configured to generate an acoustic signal; an acoustic sensor including a plurality of directional acoustic sensors arranged to have directionalities different from one another; and at least one processor configured to: obtain a directionality of the acoustic signal in a particular direction based on at least one of a sum of output signals of the plurality of directional acoustic sensors or a difference between the output signals of the plurality of directional acoustic sensors, the at least one of the sum or the difference being based on applying a weight to at least one of the output signals; and determine a distance between the acoustic sensor and a reflection surface based on a time for the acoustic signal to arrive at the acoustic sensor in the particular direction after being generated and then reflected from the reflection surface.

Abstract: The quality of ping-based ultrasound imaging is dependent on the accuracy of information describing the precise acoustic position of transmitting and receiving transducer elements. Improving the quality of transducer element position data can substantially improve the quality of ping-based ultrasound images, particularly those obtained using a multiple aperture ultrasound imaging probe, i.e., a probe with a total aperture greater than any anticipated maximum coherent aperture width. Various systems and methods for calibrating element position data for a probe are described.

Abstract: An ultrasonic transducer is described. The ultrasonic transducer comprises a membrane and a substrate disposed opposite the membrane such that a cavity is formed therebetween. The substrate comprises an electrode region and pedestals protruding from a surface of the substrate and having a height greater than a height of the electrode region, the pedestals being electrically isolated from the electrode region.

Abstract: Provided are an ultrasonic imaging method and device, and a storage medium. The ultrasonic imaging method includes: acquiring an ultrasonic echo signal; segmenting the ultrasonic echo signal into a first predetermined number of sub-echo signals according to scan depths; performing amplitude apodization on each sub-echo signal with a predetermined window function to obtain processed sub-echo signals; completing ultrasonic imaging according to the processed sub-echo signals.

Abstract: Ultrasound devices are described. The ultrasound devices may be flexibly configured to output a certain number of multilines per channel of ultrasound data and to process certain channels of ultrasound data per processing cycle. The ultrasound device may then be configured to either output more multilines per channel and process fewer channels per processing cycle, or output fewer multilines per channel and process more channels per processing cycle. In other words, the circuitry may be configured to change to a configuration with increased resolution and increased processing time or to a configuration with decreased resolution and decreased processing time.

Abstract: Systems, methods, and other embodiments associated with acoustic fingerprint identification of devices are described. In one embodiment, a method includes generating a target acoustic fingerprint from acoustic output of a target device. A similarity metric is generated that quantifies similarity of the target acoustic fingerprint to a reference acoustic fingerprint of a reference device. The similarity metric is compared to a threshold. In response to a first comparison result of the comparing of the similarity metric to the threshold, the target device is indicated to match the reference device. In response to a second comparison result of the comparing of the similarity metric to the threshold, it is indicated that the target device does not match the reference device.

Abstract: Methods and devices for imaging wells using ultrasound is described. The devices include a modular imaging device having a telemetry module and a radial imaging module and/or forward imaging module. The radial imaging module includes a ring shaped phased array ultrasonic transducer array for generating images on the length of a wellbore. Various lens and housing configurations for the radial imaging module are described. The forward imaging module includes an ultrasonic transducer comprising one or more elements and having an adjustable viewpoint for generating images of obstructions found in a wellbore. Advanced imaging modes for a radial imaging module include multiple aperture and spiral wave imaging mode.

Abstract: An ultrasonic transducer includes first and second acoustic transducers and a housing with a bottomed tubular shape. The second acoustic transducer includes an annular section supporting a second membrane section and contacting an entire periphery of the second membrane section, and an acoustic matching plate facing the second membrane section and spaced apart from the second membrane section. The acoustic matching plate is connected to a surrounding wall portion defining a sealed space with the housing. An ultrasonic transmission path sandwiched between the first membrane section and the second membrane section is provided in the sealed space. A maximum inner width of the ultrasonic transmission path is smaller than a maximum inner width of the surrounding wall portion.

Abstract: Systems and methods are provided for compressing and decompressing data in an ultrasound beamformer. The systems and methods include an encoder for compressing delay data based at least in part on a smoothness of a delay profile, and for compressing apodization data based at least in part on a smoothness of an apodization profile.

Abstract: Provided are a two-dimensional array ultrasonic probe and an addition circuit that switch an addition unit of a reception signal according to a reception channel of a main unit while preventing an increase in a chip area. The addition circuit includes, between addition output terminals that output an addition signal and transducer channels, wirings provided for each transducer channel row including the transducer channels arranged in a vertical direction on a subarray basis and coupled to the transducer channels of the corresponding transducer channel row, output switches provided for each of the wirings and coupled to the corresponding transducer channel row wiring, and an inter-output switch that couples wirings corresponding to transducer channel rows adjacent in the horizontal direction via the output switches.

Abstract: A routing protocol method for Underwater Acoustic Sensor Networks (UASNs) based on layering and source location privacy (SLP) is provided. (1) A proxy area is selected randomly by a source node. (2) A packet is delivered from the source node to the proxy area through a forwarding probability-based multipath routing algorithm, and a layer-based priority is given to candidate neighbor nodes to alleviate a long detour problem. (3) A proxy node in the proxy area is selected randomly. (4) The packet is delivered from the proxy node to a sink node through the forwarding probability-based multipath routing algorithm. (5) Steps (1) to (4) are repeated until the source node is changed or an adversary finds a position of the source node.

Abstract: A wireless audio system configured to perform an acoustic ranging operation is disclosed. The audio system comprises an audio transmitter, and audio receiver, and is configured to determine a distance between the audio transmitter and the audio receiver.

Abstract: A method for geolocating a mobile computing device within an indoor environment. One embodiment may comprise generating a geolocation request audio signal by a speaker of a first device starting at a first point in time, receiving, by a microphone of the first device, a reply audio signal from a second device, and extracting, by one or more processors of the first device, information encoded in the reply audio signal. The method may further comprise estimating, by the one or more processors, a receipt time by the first device for the reply audio signal and calculating a first time of flight (TOF) using the first point in time and the estimated receipt time for a second audio signal. The first device may comprise a smartphone and the second device may comprise a beacon located at a known location in an indoor environment.

Abstract: A system includes a tubing positionable within a wellbore and a first downhole communication device positionable to receive acoustic signals from the tubing and to transmit acoustic signals to the tubing. The system also includes a computing device in communication with the first downhole communication device and including a processor and a non-transitory computer-readable medium that includes instructions that are executable by the processor to perform operations. The operations include receiving a test message including a spectral waveform from a second downhole communication device. The operations further include determining a desired reception frequency for receiving communications from the second downhole communication device using spectral data generated from the spectral waveform. Additionally, the operations include controlling the first downhole communication device to transmit a response message to the second downhole communication device identifying the desired reception frequency.

Abstract: The present disclosure relates to a distance measurement system The system comprises a transmitter device and a receiver device. The transmitter device and the receiver device are clock-synchronized to each other. The transmitter device is configured to emit an ultrasonic signal at one or more predefined transmit times known to the transmitter and the receiver device. The receiver device is configured to receive the ultrasonic signal and to estimate a distance between the transmitter device and the receiver device based on the received ultra-sonic signal and the one or more predefined transmit times.

Abstract: An object detection system includes distance measurement sensors and a hardware processor functioning as a wave transmission control circuit and a determination circuit. The distance measurement sensors provided at different positions in a vehicle. The wave transmission control circuit sets one of the distance measurement sensors as a top of a wave transmission order. A detection range of the one of the distance measurement sensors covers a region where an object is located. The object has been detected through preliminary detection when power supply to the vehicle is started. The wave transmission control circuit then repeats a cyclic wave transmission control on the distance measurement sensors to emit ultrasonic waves sequentially in the wave transmission order. The determination circuit determines an object as a detection target object when any one of the distance measurement sensors has detected the object a predetermined number of times.

Abstract: Micromachined ultrasonic transducers having pressure ports are described. The micromachined ultrasonic transducers may comprise flexible membranes configured to vibrate over a cavity. The cavity may be sealed, in some instances by the membrane itself. A pressure port may provide access to the cavity, and thus control of the cavity pressure. In some embodiments, an ultrasound device including an array of micromachined ultrasonic transducers is provided, with pressure ports for at least some of the ultrasonic transducers. The pressure ports may be used to control pressure across the array.

Abstract: The present disclosure relates to a location determination system that includes acoustic transmitting devices and mobile devices. A mobile device receives acoustic signals (e.g., ultrasound signals) from an acoustic transmitting device. The mobile device must be able to identify the acoustic transmitting device with particularity when receiving the acoustic signals. It is more efficient to use a short identifier, for example 6 bits, for this purpose because it requires less power to transmit and decode. By utilizing the rotating identifier system described herein, more acoustic transmitting devices can be distinguished than using a time-invariant identifier would otherwise provide, and the transmissions are more secure and therefore less vulnerable to free-riders.

Abstract: A system includes a controlled acoustic source. The system also includes distributed acoustic sensors along a conduit. The distributed acoustic sensors obtain acoustic signal measurements as a function of position along the conduit in response to at least one acoustic signal provided by the controlled acoustic source. The system also includes a processing unit that generates an acoustic activity plot or report based on the acoustic signal measurements. The acoustic activity plot or report is used to identify at least one acoustic impedance boundary anomaly as a function of position along the conduit.

Abstract: A printed circuit board assembly includes a printed circuit board, a radio frequency detection circuit, and one or more damping elements. The radio frequency detection circuit is in electrical communication with the printed circuit board and defines a ring-down time interval. The one or more damper elements is mechanically coupled to the printed circuit board and has a damping coefficient that makes the duration of a mechanical ring-down time interval of the printed circuit board assembly shorter than the electrical ring-down time interval of the radio frequency detection circuit.