Abstract: A lidar, and an anti-interference method therefor, may modulate a transmitting time of the lidar by injecting random time jitter at a time interval in a sequence of the transmitting time, and cause the lidar to transmit a laser pulse according to a modulated transmitting time. When an echo received by the lidar includes an expected echo of the local lidar and an unexpected echo from other lidars, because the transmitting time and the expected receiving time of the echo are correlated, injecting random time jitter in the transmitting time of the lidar may disrupt the correlation between the transmitting time of the local lidar and the transmitting time of other lidars. Thus, when a plurality of lasers are used together in one scenario and cause crosstalk, the anti-interference method for the lidar above can be used to fight against crosstalk to some extent.

Abstract: An acoustic, preferably ultrasonic, wave emission and/or reception device, including a wave emitter configured to transmit waves at an emission frequency, and a receiver of preferably ultrasonic waves, separate from the emitter, having a resonance frequency, and configured to receive waves generated by the emitter and including direct waves and reflected waves, wherein the device includes a resonance frequency modulator of the receiver and a control unit configured to control the resonance frequency modulator during a predetermined time period, so as to reduce the sensitivity of the receiver during the predetermined time period by moving the resonance frequency of the receiver away from the emission frequency of the emitter. The acoustic device relates to the field of ultrasonic sensors, particularly PMUTs or CMUTs, having a high quality factor.

Abstract: An apparatus, a method, and computer-implemented media. The apparatus is to receive, simultaneously, electrical signals based on respective reflected frequencies of a reflected ultrasonic waveform reflected from a target object as a result of a transmitted ultrasonic waveform; compound information from the electrical signals to generate compounded electrical signals; and cause generation of an output image on a display based on the compounded electrical signals.

Abstract: The invention discloses a method for acoustic indoor positioning based on CDMA, which comprises: generating a BPSK signal; The BPSK signal was detected, the collected signal was de-carrierized and low-pass filtered, and then the data was down-sampled to the design code rate, and then the coarse position of the identification code was determined by the prefix code. Finally, the data with the same length as the identification code was intercepted from the data for matching filtering through the coarse position. Four base stations were designed in each area to obtain three TDOA observations generated by four TOA information, and the terminal position could be obtained through the three TDOA observations. Different areas are distinguished by different identification codes to achieve wide area coverage. The invention provides an effective means for accurate positioning in an indoor environment.

Abstract: Method for non-invasively characterizing a heterogeneous medium using ultrasound, comprising a step of generating a series of incident ultrasonic waves, a step of recording an experimental reflection matrix Rui(t) defined between the input emission basis (i) and an output reception basis (u), a step of determining a response REP(r,?r) of the medium between an input virtual transducer (TVin) calculated based on an input focusing of the experimental reflection matrix that creates an input focal spot around a first point (P1), and an output virtual transducer (TVout) calculated based on an output focusing of the experimental reflection matrix that creates an output focal spot around a second point (P2), said response being expressed as a function of a central point (PC) of spatial position (r) in the medium located midway between the first and second points (P1, P2).

Abstract: A stern operatively mounted universal transducer for boat includes a mounting device, having upper and lower brackets, for securement to the boat, preferably its transom, the upper and lower brackets secure a drive cylinder, which when operative, lowers a drive rod for shifting a sonic transducer upwardly above the water, or downwardly into the water to scope the surrounding underwater typography. A pair of guide rods shiftably extend through the upper and lower brackets, and at their upper ends, secure to a motor and gear housing, the guide rods at their lower ends secure to a base plate. A transducer shaft extends into the motor housing which provides for its pivoting, and at its lower end, extends downwardly through the base plate, and secures a transducer mounting plate, to which the transducer is affixed, in preparation for its usage.

Abstract: According to one embodiment, a light detector includes an element including a photodiode. A plurality of the elements are provided. The element includes a structure body for at least a portion of the plurality of elements. The structure body surrounds the photodiode and has a different refractive index from the photodiode. At least portions of the structure bodies are separated from each other.

Abstract: An ultrasound system has a set of CMUT transducer devices and drive electronics for operating a selected device of the set. The drive electronics is shared between all devices of the set. Selection is made by using a set of switches (178), with a respective switch between a DC bias output (166) of the drive electronics and an associated input (160) of each device. This provides a simple way to provide a selection function between the drive electronics and multiple ultrasound devices. In this way, the number of devices may be scale up, to cover a larger area, but without scaling the cost of the system by the same degree.

Abstract: Smart glasses including a first audio device, a second audio device, a frame including a first portion, a second portion, and a third portion, the second portion and the third portion are moveable in relation to the first portion, the second portion including the first audio device and the third portion including the second audio device, and a processor configured to cause the first audio device to generate a signal, receive the signal via the second audio device, estimate a distance based on the received signal, and determine a configuration of the frame.

Abstract: An ultrasound device is described. The ultrasound device comprises a capacitive micromachined ultrasonic transducer (CMUT). The CMUT comprises a membrane, a substrate, a cavity disposed between the membrane and the substrate, wherein the cavity comprises a bottom surface adjacent to the substrate, and non-uniform pedestals protruding from the bottom surface of the cavity into the cavity and towards the membrane.

Abstract: An optical device for determining a distance of a measurement object includes a LIDAR unit and a light sensor. The LIDAR unit has an illumination device to illuminate the measurement object and a measurement channel to detect a measurement beam reflected from the measurement object and to generate a LIDAR measurement signal. The light sensor has an optical source with a mode-locked laser to generate first and second frequency comb signals and splits the first frequency comb signal into a first measurement signal and a first reference signal and to illuminate the measurement object with the first measurement signal. The light sensor splits the second frequency comb signal into a second measurement signal and a second reference signal. An evaluation unit determines first distance information, evaluates signals detected by a measurement detector and a reference detector, generates a frequency spectrum, and determines second distance information of the measurement object.

Abstract: The invention relates to a method for determining a functional status of an ultrasonic sensor (5a) of an ultrasonic sensor device (5) for a motor vehicle (1), which is designed to emit an ultrasonic signal (8) into an environment (4) of the motor vehicle (1) and/or to receive an echo signal (9) of the ultrasonic signal (8), wherein an electrical test signal (P) is generated, which is applied to the ultrasonic sensor (5a), wherein at least one electrical characteristic parameter (K) of the ultrasonic sensor (5a) affected by the electrical test signal (P) is evaluated and as a function thereof a transfer function (13) of the ultrasonic sensor (5a) is determined, which is compared with a reference transfer function (11) and the functional state of the ultrasonic sensor (5a) is determined depending on the comparison.

Abstract: A marine survey system and method for ultrahigh resolution (UHR) mapping of a marine bottom (B) below a body of water (W) by means of a frame (20) towed as a whole by one or more towing cables (12) at a distance (Xf) behind a marine vessel (10) moving over the water (W) in a movement direction (V). The frame (20) comprises a rigid framework (23) and a plurality of independent acoustic sources (21), wherein each acoustic source (21) is independently controlled to emit a separate acoustic wave (A) propagating through the water (W) and reflecting off bottom regions of the marine bottom (B) for the mapping thereof. The acoustic sources (21) are kept fixated by the rigid framework (23) at a source-to-source distance (Ys) less than four meters in a transverse direction (Y) perpendicular to the movement direction (V) of the vessel (10) to distinguish the bottom regions with an ultrahigh resolution (Ry) of less than two meters at least in the transverse direction (Y).

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: A distance measuring device is configured to emit a transmitted wave and detect a reflected wave from an object irradiated with the transmitted wave to measure a distance to the object. At least one of the transmitted wave and the reflected wave is transmitted through a transmission window. A heater is configured to heat the transmission window from an inside of the distance measuring device. A control unit is configured to control energization of the heater according to an inside air temperature which is an air temperature inside the distance measuring device and an outside air temperature which is an air temperature outside the distance measuring device.

Abstract: A method for estimating structural vibration in real time includes steps described below.

Abstract: A method comprising: conveying a downhole tool in a tubing that is positioned in a casing that is positioned to form an annulus between the casing and a wall of a wellbore formed in a subsurface formation, wherein a cement with unknown bonding condition exists in the annulus, wherein the downhole tool includes at least one transmitter and a receiver array physically positioned in different azimuthal directions; emitting, from the at least one transmitter, a first and second acoustic transmissions in a first and second azimuthal directions; detecting, by the receiver array, a first acoustic response and a second acoustic response that is derived from the first and second acoustic transmissions, wherein the second azimuthal direction is orthogonal to the first azimuthal direction; determining a dipole wellbore resonance based on the first and acoustic responses; and evaluating a property of the cement based on the dipole wellbore resonance.

Abstract: A system including an optical scanner to transmit an optical beam towards an object. The system includes a first optical element to receive a returned reflection having a lag angle; and direct the returned reflection to generate a first directed beam. The system includes a beam directing unit to receive the first directed beam; and direct, based on a first array voltage, the first directed beam to generate a second directed beam at a first location on a different optical element. The beam directing unit to direct, based on a second array voltage, the second steered beam from the first location on the different optical element to a second location on the different optical element to compensate for the lag angle.

Abstract: Techniques are described herein that are capable of providing a modularized acoustic probe that includes multiple acoustic transducers that have discrete substrates. A first acoustic transducer is configured to generate an acoustic signal and to transmit the acoustic signal toward an object. The second acoustic transducer is configured to detect a reflected acoustic signal, which results from the acoustic signal reflecting from the object, and to convert the reflected acoustic signal to an electrical signal. The first and second acoustic transducers have respective discrete substrates. In an example, the second acoustic transducer may not be configured to generate acoustic signals. In another example, the first and second acoustic transducers may be in respective first and second rows of a two-row transducer array. In accordance with this example, the first and second acoustic transducers may be designed to have an acoustic parameter having respective first and second parameter values.

Abstract: The present invention is directed to a transducer module including a two-piece protective assembly offering mechanical protection for one or more transducer elements (i.e., transmitter(s) and/or receiver(s)) provided within. The two-piece protective assembly comprises an internal rigid housing including a cavity formed by a set of walls or projections extending from a rear portion thereof. The cavity is shaped and/or sized to receive the one or more transducer elements within. The two-piece protective assembly further includes a cover overmolded and coupled to the rigid housing and sealing the one or more transducer elements within the cavity of the housing.