Abstract: The present invention is directed to a mounting device for a fish finding apparatus and, more particularly, to a motorized mounting device which includes an adjustable length pole used to mount a sonar transducer or other device an angler may be interested in mounting to the end of the pole that enters the water. The pole is used to spin the transducer or other apparatus in a clockwise and counterclockwise direction with a switch that is adapted to be operated by the angler's foot or a wireless remote. The spin speed may also be adjusted as desired by a variable speed switch. The mounting device is configured to be secured to a boat or mounted on a boat troll motor whereby the adjustable pole is secured and spins independent of the troll motor shaft.

Abstract: A system for determining distance corresponding to positions within a sonar image is provided. The system includes transducer elements configured to transmit sonar signals into a body of water and receive corresponding sonar returns. The system further includes a device with a processor and a memory including computer program code that is configured to cause the device to receive sonar returns, generate sonar images based on the sonar returns, receive a user input selection indicating a first and second sonar position in the sonar images, determine a first chart location that corresponds to the first sonar position, determine a second chart location that corresponds to the second sonar position, determine a distance between the first and second chart location and cause the distance to be displayed on a user interface. Systems are also included herein for presenting sonar beam indicators on charts for noting the direction of the sonar beam.

Abstract: An ultrasonic probe according to an embodiment includes a group of transducer elements and a plurality of electronic circuits. The group of transducer elements constitutes a main array that is divided into a plurality of sub-arrays, and is two-dimensionally arranged. The electronic circuits are arranged corresponding to the arrangement of the transducer elements constituting the sub-array. At least one of the electronic circuits is a first electronic circuit having a first function. At least one of the electronic circuits is a second electronic circuit having a second function different from the first function.

Abstract: Sonar devices for detecting underwater objects are provided whereby a set of angled ultrasound transducers are employed to sense ultrasound signals from a plurality of different spatial regions. The angled ultrasound transducers may include a first pair of side-viewing ultrasound transducers and a second pair of ultrasound transducers configured for interrogating forward and reverse directions. The ultrasound signals from the set of angled ultrasound transducers may be processed to identify the presence of underwater objects in each spatial region, and the resulting identified underwater objects may be displayed, on a per-region basis, on a user interface. The ultrasound signals may additionally or alternatively be processed to generate a topographical model of the bed surface, and to generate a topographical surface image based on the three-dimensional topographical model. The topographical surface image may be displayed as a fly-over animation.

Abstract: Sonar devices for detecting underwater objects are provided whereby a set of angled ultrasound transducers are employed to sense ultrasound signals from a plurality of different spatial regions. The angled ultrasound transducers may include a first pair of side-viewing ultrasound transducers and a second pair of ultrasound transducers configured for interrogating forward and reverse directions. The ultrasound signals from the set of angled ultrasound transducers may be processed to identify the presence of underwater objects in each spatial region, and the resulting identified underwater objects may be displayed, on a per-region basis, on a user interface. The ultrasound signals may additionally or alternatively be processed to generate a topographical model of the bed surface, and to generate a topographical surface image based on the three-dimensional topographical model. The topographical surface image may be displayed as a fly-over animation.

Abstract: The invention relates to a fill level measurement device for determining a topology of a bulk material surface, comprising a foldable antenna assembly. The antenna assembly has a folded and an unfolded state. In the folded state, the antenna assembly can be pushed through a relatively small container opening when the measurement device is being fitted to a container. The antenna assembly is unfolded after the measurement device has been attached. This can make fitting less complex.

Abstract: Embodiments of the invention provide a dermatological cosmetic treatment and imaging system and method. In some embodiments, the system (20) includes a hand wand (100) with at least one finger activated controller (150, 160), and a removable transducer module (200) having an ultrasound transducer (280). In some embodiments, the system (20) can include a control module (300) that is coupled to the hand wand (100) and has a graphical user interface (310) for controlling the removable transducer module (200), and an interface (130) coupling the hand wand (100) to the control module (300). The interface (130) may provide power to the hand wand or may transfer a signal from the hand wand to the control module. In some embodiments, the cosmetic treatment system (20) may be used in cosmetic procedures on at least a portion of a face, head, neck, and/or other part of a patient.

Abstract: Techniques are disclosed for systems and methods to provide touch screen sonar adjustment for mobile structures. A sonar adjustment system includes a user interface with a touch screen display and a logic device configured to communicate with the user interface and a sonar system. The user interface is configured to receive and/or display sonar data provided by the sonar system. The logic device is configured to determine a stimulus or scroll rate component and a sample scale component of a pinch gesture performed on the touch screen display, adjust a rate and/or a sample scale factor for the touch screen display and/or for the sonar system, and render the sonar data according to the adjusted rate and/or sample scale factor. The user interface and logic device may be integrated together to form a multifunction display used to power and/or supply sonar transmission signals to the sonar system.

Abstract: During normal and reverse swings of a transducer main body, an engagement accuracy is ensured to reduce generation of vibration and noise. An ultrasonic transducer includes: a coupling swingably and loosely fitted between one end portion of an output shaft of a power source that swings the transducer main body and the transducer main body, and a flywheel swingably and loosely fitted to another end portion of an output shaft of the power source, ensuring the reduced vibration and noise from the transducer main body.

Abstract: The present invention provides an auxiliary berthing method and system for a vessel. In the berthing method, by a solar blind ultraviolet imaging method, a position and an attitude of a vessel relative to a shoreline of a port berth during berthing are calculated by at least two solar blind ultraviolet imaging modules according to light signals received by a solar blind ultraviolet light source array arranged in advance on the shore. Further, when more than three solar blind ultraviolet imaging modules are used, in the method and device of the present invention, a normalized correlation algorithm and a data fusion algorithm are used to improve the accuracy of the position and attitude data of the vessel.

Abstract: Systems and methods for measuring the thermal crown of rolls in-situ (e.g., at high temperature) either inside or outside the rolling mill can include sensors that measure propagation times of mechanical waves through the rolls. In some embodiments, one or more sensors are used to measure the propagation times of ultrasonic waves traveling inside the roll and normal to the roll's axis. These measurements can be taken when the roll is still hot and can be used to determine in real-time the thermal expansion at various points along the roll.

Abstract: A vibration source estimation device, method and computer-readable medium are provided. The vibration source estimation device comprises a processor configured to execute instructions to receive data samples of a plurality of vibration signals generated at a vibration position, the data samples being associated with a plurality of frames. The processor is also configured to execute instructions to calculate a cross correlation function for each frame based on the data samples, calculate a weight for each frame based on a signal-to-noise ratio calculated from the cross correlation function, multiply the cross correlation function for each frame by the weight, calculate a sum of weighted cross correlation functions for respective frames as a weighted-cross-correlation function, and estimate the vibration position based on the weighted-cross-correlation function.

Abstract: An environment measurement system according to the present invention is provided with a first unit comprising: a transmitter which is located undersea and transmits an acoustic wave in a designated direction a plurality of times; a first receiver which is located undersea and receives an acoustic wave reflected by a reflecting body at the sea surface or the seabed; a transmission direction setting unit which designates, to the transmitter, transmission directions specified in advance by a user, so as to cause the transmitter to transmit acoustic waves in the directions; a first necessary time measurement unit which, for each of the transmission directions, measures from the transmission and reception times of an acoustic wave a time necessary for the acoustic wave to return, as a necessary time, and outputs an average of the measured necessary time as an average necessary time for each of the transmission directions; a layer setting unit which partitions between the sea surface and the seabed into layers each

Abstract: A sector-scanning sonar imaging system with at least one sonar imaging element housed within a transducer housing coupled to a self-reciprocating mechanism, and a drive mechanism housed within a waterproof housing. The oscillating motion of the transducer housing produces a highly-detailed, photo like sector scan sonar image of the bottom and other objects surrounding the boat on which it is mounted. The drive mechanism housing may be rigidly attached to either a boat hull or to a trolling motor. The sonar imaging element housing may be removably attached to the drive mechanism, and shielded by an acoustically transparent shroud to protect the elements from damage. The sector-scanning sonar imaging system connects to a control head with display either directly, or through some other communications protocol, such as a wireless protocol.

Abstract: A searchlight sonar is installed on a ship (11) and searches under water around the ship (11) while changing the transmitting direction of an ultrasonic beam (TB) at a predetermined split rotation (Mn) in the circumferential direction around the ship (11). The split rotation (Mn) is set to increase as the depression angle of the transmitting direction of the ultrasonic beam (TB) is increased.

Abstract: This invention discloses a real-time phased array 3D acoustic imaging sonar processing system and method. The system comprises a 3D sonar dot data collection module, a 3D sonar dot data uploading module and a real-time 3D sonar dot data processing module of PC terminal; the method includes the following content: make use of two-stage FPGA signal processing to realize real-time formation of electronic focusing wave beam, and acquire 3D sonar dot data; further transmit 3D sonar dot data to PC terminal for setting and acquisition of directives; PC terminal aims to receive 3D sonar dot data for real-time processing: This includes real-time single-frame multilayer reconstruction, image registration and splice, 3D visualization and real-time saving of data. This invention features in compact structure, high real-time precision, clear image, easy alternation and high extendibility, which has effectively realized the real-time 3D processing of sonar targets.

Abstract: A 360-degree sonar imaging system and method are provided. The system includes a sonar transducer assembly pod with tilted mechanically scanning sonar (MSS) transducers that is deployed into the water below the bottom of the boat. The system provides photo-like imaging of an area surrounding a boat which does not require the boat to be in motion. The pod is deployed by a variety of manual, (trolling motor, transom) or powered mechanical (bow, transom, or fairing block) deployment mechanisms to allow for deployment and retraction of the sonar transducer assembly. In particular embodiments, the MSS system communicates with a side-scan-sonar-imaging-equipped control head unit to display the images generated therefrom. Various speeds and sector scans are provided, as well as a locked side-scan sonar mode. Waypoint navigation and split screen views are also provided.

Abstract: A method for seismic surveying includes disposing a plurality of seismic sensors in a selected pattern above an area of the Earth's subsurface. A seismic energy source is repeatedly actuated proximate the seismic sensors. A signal used to actuate the source comprises a linear chirp having a starting frequency and an ending frequency less than twice the starting frequency. Recorded signals are processed to generate an image corresponding to at least one point in the subsurface, the processing includes stacking recordings from each sensor for a plurality of actuations of the source, cross correlating the stacked signals with an expected signal generated by non linearities in the subsurface and beam steering a response of the seismic sensors such that the at least one point is equivalent to a focal point of a response of the plurality of sensors.

Abstract: A transducer 1b comprising a vibrator body 2b for generating and/or receiving acoustic or ultrasonic waves, acoustically coupled to a second part 4 for generating and/or receiving acoustic or ultrasonic waves and, a matching layer 5 coupled to said vibrator body 2 so as, in use, to acoustically match the vibrator body 2b to a medium 6 contacting said matching layer 5.

Abstract: A device for conducting ultrasonic inspections comprises a base. In addition, the device comprises a probe housing pivotally coupled to the base with a suspension system. Further, the device comprises an ultrasonic probe disposed within the probe housing and configured to transmit ultrasonic signals. The suspension system is configured to permit the probe housing to pivot relative to the base to transmit ultrasonic signals in a plurality of directions.

Abstract: A method for pre-determining an underwater objects GPS position using a rotatable scan sonar unit linked to a boat, magnetic compass and GPS receiver. This system determines the underwater objects GPS position using the objects distance, compass heading and a GPS receiver/sonar on a boat. This system will provide real time longitude and latitude positions of underwater objects seen with sonar at a distance from a boat, and will allow for precise autopilot navigation or fixed position fishing. The system can also be used to correct for GPS errors when using previously stored waypoints positions of an object. The computer determines an objects underwater GPS position using a sonar transducer and mounted on a 360 degree movable mechanism such as a trolling motor unit, or phased array of transducers and a compass to provide heading information and formulates the objects position based on the distance and heading of the object in relation to the boats current GPS position.

Abstract: Acoustic arrays transmitting and/or receiving multiple, angularly dispersed acoustic beams are used to generate 2D and 3D images. The acoustic arrays may comprise frequency-steered acoustic arrays provided in one-dimensional linear and two dimensional planar and curvilinear configurations, which may be operated as single order or multiple order arrays, may employ periodic or non-periodic transducer element spacing, and may be mechanically scanned to generate 2D and 3D volumetric data. Methods and systems for operating acoustic arrays in a frequency-steered mode in combination a mechanical beam steering mode, electronic time-delay and phase shift beam forming modes, and phase comparison angle estimation modes are also provided. Methods for generating two and three dimensional images of underwater target scenes using multi-beam acoustic imaging systems are disclosed.

Abstract: A system for measuring an acoustic property of material penetrated by a well borehole. The system uses a borehole logging tool comprising preferably one acoustic transmitter and preferably a plurality of acoustic receivers. An independent measurement is used to determine azimuthal orientation of the tool within the borehole. Firings of the transmitter are based upon azimuthal orientation of the tool. Receiver responses resulting from preferably a plurality of transmitter firings per tool revolution are combined to form at least one composite transmitter response. The composite receiver response is compensated for adverse effects of the tool operating eccentered within the borehole.

Abstract: A method utilizing an ultrasonic distance sensor to measure distances between the sensor and an object includes the steps of: identifying an object using a first object tracking apparatus; adjusting a first rotation direction of the first object tracking apparatus to pinpoint the object; measuring a distance between the object and the first object tracking apparatus; and obtaining a location of the object in accordance with the distance and the first rotation direction.

Abstract: A vessel-mountable integrated sonar system is provided. The vessel-mountable integrated sonar system comprises at least one imaging sonar data acquisition device and at least one processing system electronically and removably connected to the at least one imaging sonar data acquisition device, wherein the sonar data acquisition device preferably provides acoustic data to the processing system, producing sonar imageries utilizing the acoustic data, and wherein the system provides digital tilt and azimuth direction feedback for accurate geo-referencing of data to localize targets of interest.

Abstract: An ultrasonic scanner has an encoder contacting a drum containing an array. The scanning assembly can be replaced via a snap fit formation. The encoder and drum are resiliently biased and movable relative to the chassis. The array can also be movable relative to the chassis.

Abstract: A cleaning robot may be provided having a case and a sensor assembly. The sensor assembly may include a sensor hole having a first opening provided at an outer surface of the case and a second opening provided inwardly of the first opening, with respect to a center of the case. Additionally, the sensor assembly may include a sensor element configured to receive a signal and the sensor element may be provided inwardly of the first opening.

Abstract: A method of generating an audio signal comprises receiving a plurality of input audio signals from a plurality of microphones forming a microphone array, the plurality of input audio signals being representative of a set of sound sources within the auditory field of view of the microphone array at a given instant in time; receiving a motion input signal from a motion sensor, the motion input signal being representative of the motion of the microphone array; and manipulating the received plurality of input audio signals in response to the received motion input signal to generate an audio output signal that is representative of a set of sound sources within the auditory field of view of a virtual microphone, the apparent motion of the virtual microphone being independent of the motion of the microphone array.

Abstract: A medical diagnostic ultrasound system comprises several subsystems, such as a transmit beamformer, a receive beamformer, a B-mode processor, a Doppler processor and a scan converter. These subsystems are within the ultrasound data processing path for processing ultrasound data. One or more of these subsystems are implemented with one or more re-programmable logic devices. For example, one or two field programmable gate arrays are used is each subsystem to perform most or almost all of the subsystems essential functionality.

Abstract: A vessel-mountable integrated sonar system is provided. The vessel-mountable integrated sonar system comprises at least one imaging sonar data acquisition device and at least one processing system electronically and removably connected to the at least one imaging sonar data acquisition device, wherein the sonar data acquisition device preferably provides acoustic data to the processing system, producing sonar imageries utilizing the acoustic data, and wherein the system provides digital tilt and azimuth direction feedback for accurate geo-referencing of data to localize targets of interest.

Abstract: A vessel-mountable integrated sonar system is provided. The vessel-mountable integrated sonar system comprises at least one imaging sonar data acquisition device and at least one processing system electronically and removably connected to the at least one imaging sonar data acquisition device, wherein the sonar data acquisition device preferably provides acoustic data to the processing system, producing sonar imageries utilizing the acoustic data, and wherein the system provides digital tilt and azimuth direction feedback for accurate geo-referencing of data to localize targets of interest.

Abstract: An ultrasonic imaging apparatus and method combines dynamically focused reception and coded transmission/reception technologies by inexpensive circuitry. A receive aperture is divided into smaller apertures. Correspondingly, a receive beam former is divided into receive sub-beam formers 36a to 36n by which a phase alignment and summing process is performed. Thereafter, coded signals are compressed in decoders 37a to 37n in a time axis direction. Output signals from the decoders are once again subjected to a phase alignment and summing process in a second beam former.

Abstract: An automatically tracking scanning sonar alternately performs horizontal scanning and vertical scanning and a target lock processor calculates a predicted position of a target based on an echo signal previously received from the target when the echo signal from the target is interrupted. A selector sets a range, tilt angle and sounding direction and outputs them to a transmit-receive controller such that the scanning sonar can scan the predicted target position. As the depth of the target is determined by performing the vertical scanning, the tilt angle of an umbrellalike beam pattern produced by the horizontal scanning can be varied to follow the target by controlling the tilt angle based on target depth information even when the target moves in vertical directions. It is therefore possible to automatically track the target in a reliable fashion.

Abstract: A sonar array comprising a support structure, an acoustic projector attached to the support structure, and a plurality of directional hydrophones attached to the support structure and arranged so as to surround the acoustic projector. The directional hydrophones are equidistantly spaced about the acoustic projector. In one embodiment, the array includes means attached to the support structure that allows the support structure to be connected to a device that effects course steering of the sonar array.

Abstract: A manual scan sonar integrates multiple technologies into a compact and low cost single beam sonar having the ability to generate wide sector views comparable to that of much larger and more expensive multiple-beam sonar units. The manual scan sonar uses a piezoelectric transducer, orientation and motion sensors, a power preamplifier and amplifier, and a microcomputer with a display, all contained within a compact waterproof housing. In operation, the user scans the sonar across an area, and the orientation and motion sensors monitor the user's natural human motion to provide bearing information which is processed and stored by the microcomputer. The ultrasonic information provided by the sound echoes is displayed on the display screen of the computer as a continuous sector. This sonar may be adapted for either diver-held or topside use.

Abstract: The device comprises a transmitter (7) transmitting ultrasound into a predetermined space (5), a sensor (8) which senses the echoes from the transmission by the transmitter into the space in order to deliver a signal representative of the echoes, and electronic device for processing the signal in order to diagnose the possible presence of a moving body in the space (5). It further comprises a) device (10) for scanning the space (5) with the ultrasound beam output by the transmitter (7) and (b) device (11) for simultaneously moving the echo sensor (8) so as to optimize the signal/noise ratio of the output of the sensor (8).

Abstract: The system provides three-dimensional real time imaging, with features that serve to control acoustic effects that cause interference. Systems are disclosed for medical imaging and other applications in fields that utilize radiated wave signals. The system includes visualization methods to enable guidance of surgical instruments as well as general medical diagnostic usage. The present invention uses a beamformed television method which achieves visual format imaging. Beamformed television includes orthogonal arrays to efficiently resolve two dimensions of a scene with measures to control grating lobes. Beamformed television also includes a method that reduces the time to transmit and receive signals by use of a single burst transmission of multiple frequency codes from each transducer which causes multiple, coded transmit beams that are radiated simultaneously. The addition of step chirp operations achieves highly precise range resolution which makes visual format imaging possible at selected ranges.

Abstract: A method of and apparatus for determining the topography and/or volume of a layer of sludge on the bottom of an oil tank, for example, in which a sonar head having a velocimeter is immersed in the oil, and a fan-shaped beam of acoustic energy is swept across the layer of sludge. Also the velocity of sound in the oil is measured, preferably at a plurality of heights over a relatively short vertical range to determine the velocity gradient, which is then extrapolated for the entire depth of the oil. Processing means determine, from the extrapolated velocity gradient, the topography and/or volume of the sludge. The method provides an accurate indication of the distribution and volume of sludge across the whole of the bottom of an oil tank, taking into account changes in the speed and attenuation of acoustic energy due to, for example, the temperature gradient in the oil.

Abstract: An acoustic ranging and detection system comprises an acoustic transmitter for producing an acoustic ranging signal and first and second acoustic receivers positioned on either side of the acoustic transmitter. A support mounts the acoustic transmitter and both acoustic receivers for concurrent rotation about a central axis passing through the acoustic transmitter. A first motor is connected to the first acoustic receiver and is adapted to impart independent rotative movement thereto. A second motor is connected to the second acoustic receiver and is adapted to impart independent rotative movement thereto. A control system is responsive to echo signals from a target that are received by the first and second acoustic receivers to rotate the support to point the transmitter at the target and further operates the first and second motors to cause the respective acoustic receivers to be repositioned so as to manifest receiving beam patterns which exhibit central axes that intersect in the region of the target.

Abstract: A method for detecting and characterizing flaws in an object having an arbitrary-shaped geometry. The present invention uses a synthetic aperture focusing technique (SAFT) which enables maximum aperture imaging. Maximum aperture imaging is attained by determining whether a plurality of reconstruction points within an object are in the width of a transmitted ultrasonic sound wave.

Abstract: A self-steering platform system incorporates at least three and preferably four microphones circumferentially spaced about the platform which is mounted for movement preferably around two mutually perpendicular axes. A sound source is selected and separate audio signals from the microphones are analyzed by a control which based on differences between the signals from the microphones emanating from the selected source determines the location of the selected source. The orientation of the platform is then adjusted by the control relative to the selected sound source. The present invention is particularly useful for mounting a shotgun or parabolic microphone to enhance sound from a selected source.

Abstract: An ultrasonic scanning device includes an ultrasonic sensor mounted for rotation. The sensor can be automatically oriented in a predetermined reference position from a random position. During a scanning operation the sensor is rotated by incremental angles. The length of the angles is changed after a predetermined time elapse following the initiation of a scanning operation.

Abstract: An improved method for repair of incore-instrumentation-housing and related defects in a nuclear reactor system involves three stages, each with ultrasonically assisted inspections. In the first stage, a defective incore housing is removed and the exposed area and aperture at the former location of the incore housing is ultrasonically inspected using an ultrasonic probe with a tiltable disk-shaped head that self-conforms to the local contour of the reactor vessel bottom. In the second stage, a weld buildup is formed. The reactor is then sealed and the weld buildup is machined to define an aperture therethrough. The weld buildup is then ultrasonically inspected with a second probe with a centering member that is stationary as the probe body is moved vertically relative to it. In the third stage, a J-prep is formed. A new incore housing is inserted through the weld buildup aperture. The new incore housing is welded at the J-prep. The J-weld is ultrasonically inspected using a third ultrasonic probe.

Abstract: An ultrasonic scanning device includes an ultrasonic sensor mounted for rotation. The sensor can be automatically oriented in a predetermined reference position from a random position. During a scanning operation the sensor is rotated by incremental angles. The length of the angles is changed after a predetermined time elapse following the initiation of a scanning operation.

Abstract: A side-look sonar system and method apply a spotlight-mode synthetic aperture technique to provide increased image resolution and a long receive aperture. A control circuit activates mechanical drives to rotate projecting and receiving sonar transducers as the carrier vehicle on which the transducers are mounted moves relative to a target. The mechanical drives rotate the transducers as a function of the rate of movement of the carrier vehicle to direct receiving and projecting surfaces of the transducers at the target for an extended period of time. An image processor uses conventional beamforming techniques to form a high resolution image of the target based on the acoustic energy samples acquired by the receiving transducer.

Abstract: A synthetic Mill's Cross scanner array is provided for a sonographic system. The array includes orthogonal lines for which projector and hydrophone are respectively provided. During a scan of a target volume, the projector and the hydrophone elements are moved from first paired positions to second paired positions, etc. to n paired positions. Data from the scan is processed to provide three-dimensional data for displaying the target volume.

Abstract: The objects of the present invention are achieved by a method and means for temporarily suspending sonar beam transducer means on a dihedral wing body at a first underwater location within sonar beam range of said scoured area; scanning a first portion of said scoured area with said sonar beam in a first substantially vertical plane that points in a first azimuth direction, so as to generate signals indicative of the range and bearing of said scanned first portion from said transducer means; and scanning at least a second different portion of said scoured area with said sonar beam in a second different substantially vertical plane that points in a second different azimuth direction, so as to generate signals indicative of the range and bearing of said scanned second portion from said transducer means. In actual practice, scanning by the sonar beam occurs in many different vertical planes and also can be done from different underwater locations.

Abstract: A side-looking fish finding apparatus transmits a sonar pulse approximately horizontally into a body of water, and then monitors echoes from the pulse. The time interval between successive sonar pulses is varied in a random manner in order to permit two or more similar units to be used in close proximity to each other without significantly interfering with each other. An individual echo is treated as the detection of a fish if it has a magnitude above a predetermined threshold, if it has a length within a predetermined range bounded by upper and lower limits, if it is preceded by a leading space interval free of other echoes and having a predetermined duration, if it is followed by a trailing space interval free of other echoes and having a predetermined duration, the duration of the trailing space interval being less than the duration of the leading space interval, and if an equivalent echo is received in response to each of the next four successive sonar pulses.

Abstract: The invention generally pertains to apparatus for determining bedload thickness of a bedload on a bed surface in an aquatic medium. An acoustic source is operative when energized for producing incident acoustic waves in the medium directed at the bed surface resulting in reflected waves. An acoustic sensor is movably locatable between the acoustic source and the bed surface and is responsive to the incident and reflected waves for producing a variable output representative of the sum of the incident and reflected waves. The sum varies between a maximum and a minimum with distance from the bed surface. A height sensor is responsive to the position of the acoustic sensor relative to the bedload thickness for producing an output indicative thereof. A processor responsive to the acoustic sensor output and the height sensor output produces an output indicative of the thickness of the bedload thickness.

Abstract: A two-dimensional phased array ultrasound imaging system distributes signal delays between its probe and its base section. The transducer elements are grouped and relative delays between elements of a group are introduced within the probe. Once the intragroup delays are introduced, the signals from the elements of a group are combined to generate a group signal. A group signal is generated for each group and, collectively, the group signals are transmitted to the base section via a multi-wire cable. Delays between groups are introduced at the base section. This distribution of delays maintains power dissipation within the probe at a tolerable level while requiring only a manageable number of data and signal lines between the probe and base section.