Abstract: Methods and systems for improved data transmission using audio transmissions are provided. In one embodiment, a method is provided that includes receiving an audio transmission at. Audio symbols may be identified within the audio transmission, and a magnitude and phase for each of the symbols may be identified. Based on the magnitudes and phases, corresponding data values may be identified for each of the audio symbols and may be combined to form a data payload of the audio transmission.

Abstract: An integrated acoustically generator-based system having a substrate, a plurality of micro generators (conversion apparatus) disposed on the substrate, the micro generators each generating a voltage output in response to acoustic vibrational energy received from the acoustic source, and at least one power processor disposed on the substrate, and the power processor being electrically coupled to outputs of the plurality of micro generators.

Abstract: An efficient, broadband, underwater acoustic transducer having nominally a quasi-omnidirectional radiation pattern is realized with a plurality of thin walled radially vibrating hollow spherical piezoelectric transduction elements aligned axially. Each spherical transduction element is progressively smaller in diameter so as to enhance the combined frequency coverage and achieve the desirable radiation pattern. The transduction elements may be excited individually, or together electrically in series or in parallel combinations.

Abstract: To provide an adaptive array control device, method, and program adapted to be able to output an enhanced target signal by precisely carrying out a coefficient update control of a plurality of signals input from a group of sensors arranged in an array, the coefficient update control being less influenced by the frequency characteristics of the signals and directions of a target signal and interference. The invention includes: a gain control section 900 having an analyzing section 903 which analyzes characteristics of a target signal and a correcting section 905 which corrects a target signal power estimated value in response to the analysis result; and blocking matrix circuits 310 and 320 which receive and process signals from a plurality of sensors having different intervals.

Abstract: A method for determining the position of an underwater device includes placement of a plurality of station keeping devices on or below the surface of the water in known positions. A device to locate is provided for placement below the surface of the water, and the device to locate and the station keeping devices are provided with a synchronized time base and a common acoustic pulse time schedule. Each station keeping device sends an acoustic pulse at a time according to the common acoustic pulse schedule. The device to locate receives pulses sent by the station keeping devices and calculates a distance between itself and each station keeping device based upon the time that the acoustic pulse is sent and the time that the pulse is received. The device to locate then calculates its position based upon the distances between the device to locate and the station keeping devices.

Abstract: Systems and methods are provided for locating threats to an aircraft that are located on the ground. Associated bearings are determined from an aircraft for each of a plurality of detected shots from a threat at ground level. A plurality of pairs of bearings are selected, and a weight value is calculated for each selected pair of bearings. An estimated position for the threat is determined from each selected pair of bearings. An improved estimation of the position for the threat is calculated as a weighted combination of the estimated positions.

Abstract: The system generates resonant ultrasonic vibrations, preferably in a torsional mode. A control circuit monitors, feedback signals therefrom, which are scanned to determine the frequency at which minima occur. The frequency of the ultrasonic signal is then adjusted to the frequency at which the minimum occurs.

Abstract: A sonar transducer network for observing a seabed includes a controller. A first transducer assembly includes a first acoustic transducer to convert a first ping to a first electrical signal; and a first transducer processor to receive a first electrical signal from the first acoustic transducer to generate the first transducer data. At least one second transducer assembly is spaced apart from the first transducer assembly. The second transducer assembly includes a second acoustic transducer to convert a second ping to a second electrical signal. The second transducer processor receives the second electrical signal from the second acoustical transducer to generate second transducer data. A network bus communicates first transducer data and second transducer data with the controller.

Abstract: In an embodiment, a process measures a velocity of a vessel using a spatial correlation sonar hydrophone array. The process includes the step of selecting a correlation time such that a correlation occurs between an early pulse and a later pulse on a first hydrophone and a second hydrophone respectively, wherein the first hydrophone and the second hydrophone are maximally separated in the spatial correlation sonar hydrophone array. The process further includes the step of selecting a time spacing between a first pulse and a second pulse such that the spacing is a function of the correlation time and a constant, wherein the constant is proportional to a size of the spatial correlation sonar hydrophone array, and wherein the correlation time is an approximate multiple of a sum of a time between the first pulse and the second pulse and a time between the second pulse and a next first pulse.

Abstract: In various embodiments, the invention pertains to systems for acoustic beamforming that include one or more speaker membranes, such as, for example, a continuous ribbon membrane, and several independently addressable drivers. Moreover, certain embodiments relate to methods for beamforming with improved directionality.

Abstract: An object detecting apparatus detecting an object position based on a reflected wave generated by reflection of a transmitted ultrasonic wave from the object includes a transmitting portion transmitting the ultrasonic wave, a receiving portion receiving the ultrasonic waves as received signals, a detecting position detecting an envelope and an operation portion detecting a peak of each envelope and obtaining an approximate line with a maximum change amount of the envelope in a change amount increasing period set to a gradient of the approximate line, provided that the change amount increasing period is defined as a period that an amount of change per a predetermined unit time of the envelope, heading to the peak, continues to increase, the operation portion obtaining a time that a voltage value of the approximate line equals a reference value as a receipt time and detecting the object position based on the receipt time.

Abstract: An example of a cable positioning mechanism for directing a cable into a seismic sensor housing for connection with the seismic sensor includes a member sized to connect with a seismic sensor housing, the cable passing through the member at opposing anchor points for operational connection to the seismic sensor between the anchor points, wherein the cable is oriented through the member at an angle that is not perpendicular to a vertical axis of the sensor housing.

Abstract: This invention includes a first electrode which is fixed on a base, a vibration film which is disposed to oppose the first electrode with an air and vacuum portion between the vibration film and the first electrode, a second electrode which is supported by the vibration film and is connected to a predetermined potential, a ferroelectric which is electrically connected to the first electrode, and a driving portion that applies, to the first electrode, a driving signal which is a monopulse voltage signal and whose polarity is reversed every time the driving signal is outputted.

Abstract: A system and method for implementing non-lethal chemical warfare against rampage shooters. A sound detection module detects a sound of a gunshot from at least one of a collection of sensors within a building. A sound location module determines a location of the gunshot by analyzing the sound. At least one emitter releases non-lethal chemical countermeasures from at least one at the location of the gunshot.

Abstract: Embodiments of the present invention relate to a linear submersible body including a plurality of rigid segments that are articulated and can adopt relative to one another an orientation making it possible to form a rectilinear body, or a curved body of which the radius of curvature is adapted to the drum of the winch onto which it is wound. The segments are associated with couplers and configured so that a vertical rectilinear posture is naturally obtained when the device is totally submerged and towed by the ship, while the curved posture is obtained naturally by the winding of the device onto the winch. Embodiments of the invention apply to the production of linear and vertical transmitting acoustic antennas.

Abstract: An ultrasound position determination system includes a base unit and at least one mobile unit. Each of the mobile and base units are operable to transmit and receive ultrasonic signals. The mobile unit is adapted to transmit a predetermined signal in dependence upon the state of transmission of the base unit. The base unit is adapted to determine the time taken for the signal to pass from the mobile unit to the base unit and thereby calculate a distance between the mobile unit and the base unit.

Abstract: A navigation system extends satellite navigation to divers, underwater vehicles, and surface vessels. The navigation system comprises a location reference unit and a plurality of sub-surface beacon units. The location reference unit includes a receiver to receive navigation signals from earth-orbiting satellites and/or an inertial navigation system. The location reference unit further includes control circuits to communicate with to sub-surface beacon units and to transmit location information to said sub-surface beacon units, and a transceiver to transmit location information to the sub-surface beacon units. The beacon units include control circuits to determine the location of the beacon unit based on location information received from the location reference unit, and a transceiver to receive location information from the location reference unit and to transmit location information to a guided unit to provide navigation assistance to the guided unit.

Abstract: A method and system for locating a sound source within a defined area in which the sound data is collected with a plurality of spaced apart microphones. The sound data received by the microphones is processed to form a cross spectral density matrix containing vectors of cross correlations and auto correlations of the sound data. A replica vector matrix containing sound data from at least one test sound at a plurality of predetermined locations within the defined area is then constructed. The sound data vectors in the cross spectral density matrix are then projected on the replica vectors in the replica vector matrix to obtain a probability of the location of the sound source at each predetermined location within the defined area. These probabilities form a distribution within the defined area in which the largest probability distribution correlates with the location of the sound source.

Abstract: A method and apparatus for enhancing explosive yield is provided. The apparatus generally includes an energetic charge operatively associated with a guide. The guide is operatively associated with a reactive material. According to an aspect of the method, the energetic charge is activated to produce a shockwave to impact a reactive material. The shockwave is focused by the guide to impact the reactive material. Impacting the reactive material releases energy in the reactive material to enhance the yield of the energetic charge.

Abstract: An artificial disc for replacement of a spinal three-joint complex of a mammal includes a generally spinal disc-shaped upper plate having an anterior section and a posterior section and a generally spinal disc-shaped lower plate also having an anterior section and a posterior section. The anterior section of the upper plate is selectively separable from the posterior section of the upper plate and the anterior section of the lower plate is likewise selectively separable from the posterior section of the lower plate. A ball is interposed the lower face of the upper plate and the upper face of the lower plate and a plurality of posts, each projecting from one of the faces toward the other of the faces corresponds to a plurality of detents provided on the one of the faces opposite the face from which the corresponding post projects for engaging the posts.