Abstract: A method of readjusting sonar images using sub-antennae. For each point of the bottom, a sub-antenna is constructed of a given size at one end of the physical antenna. A first channel is constructed over a short time slice centered on the point. A sub-antenna is also constructed upon recurrence No. 2 of the same size as the first one, but at the opposite end of the physical antenna. With the second sub-antenna, a plurality of second channels is formed over a sector which is sufficiently wide to contain the point. These second channels are intercorrelated with the first channel so as to adopt the one which maximizes the intercorrelation peak. This procedure is repeated for different sub-antenna sizes and one is adopted which produces the maximum of the preceding intercorrelations.

Abstract: A microwave detector for detecting a target microwave signal carries out detection by dividing the target bandwidth into a plurality of partitioned bands which are each repeatedly swept a prescribed number of times, with the detected wave outputs from each sweep being added together to form an added detected wave output for each partitioned band, and due to mutual cancellation of the white noise, the presence of even a faint target microwave signal within a partitioned band will increase to a detectable level in the added detected wave output of such partitioned band, and because the detection process is carried out separately for each partitioned band, the microwave detector only needs enough memory capacity to store the added detected wave output of a single partitioned band.

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: A method for imaging a target includes the steps of transmitting ultrasonic energy at a fundamental frequency and receiving reflected ultrasonic energy at a harmonic of the fundamental frequency. The ultrasonic energy is transmitted in power bursts, each having a respective envelope shape, wherein the envelope shapes rise gradually to a respective maximum value and fall gradually from the respective maximum value. Ultrasonic energy in the transmit beam is focused in an elongated high power region, as for example by means of a line focus.

Abstract: The invention concerns an ultrasound parking aid system which emits warning signals when an echo signal lying within an audibility window exceeds a given threshold value. Hitherto, an audibility window or the sensitivity of the system was adapted to fixed data of the vehicle and/or the roadway. According to the invention, the sensitivity, audibility window or even the emission response is adapted as a function of varying dynamic data of the vehicle or roadway.

Abstract: A personal emergency location system (PELS) employs a small battery-powered personal unit worn by a person who may be lost overboard. The personal unit has a GPS receiver and processor for determining the person's GPS location coordinates, and an RF transmitter for sending an RF emergency signal with the GPS coordinate data to a nearby vessel within a short range. The nearby vessel is equipped as a base station to receive the RF emergency signal and the person's GPS coordinate data and send out an RF broadcast signal of the person's position over a long range to the authorities or other rescue vessels. The personal unit is updated with the most current GPS data and recharged during inactive periods when the person on-board a vessel equipped as a base station. The personal unit sends the emergency signal until an acknowledgment signal is received from a base station, whereupon the personal unit is placed in a “Receive-Only” mode to save battery power.

Abstract: A method for imaging a target includes the steps of transmitting ultrasonic energy at a fundamental frequency and receiving reflected ultrasonic energy at a harmonic of the fundamental frequency. The ultrasonic energy is transmitted in power bursts, each having a respective envelope shape, wherein the envelope shapes rise gradually to a respective maximum value and fall gradually from the respective maximum value. Ultrasonic energy in the transmit beam is focused in an elongated high power region, as for example by means of a line focus.

Abstract: Apparatus for determining positional information for an object transmits a probe signal towards the object. The probe signal as returned by the object is received at a plurality of spaced apart locations. The relative timing of the returned probe signals as received at the plurality of locations is detected, whereby positional information for the object can be determined. A number of realizations of the invention are disclosed.

Abstract: A system for determining the sound velocity profile in a medium, such as water, includes an acoustic signal transmitting system at a transmitting location and an acoustic signal receiving and processing system at a receiving location. In one example, the acoustic signal receiving and processing system is located in a submarine or other similar vessel, and the acoustic signal transmitting system is located in an expendable vehicle or probe that moves throughout the water surrounding the submarine or vessel. At one or more transmission times and transmitting locations, the acoustic signal transmitting system transmits an acoustic signal. The acoustic signal receiving and processing system receives each acoustic signal at an arrival time and determines the sound velocity in the water between the transmitting location and the receiving location using the arrival time, the predetermined transmission time, and the predetermined transmitting location.

Abstract: An weapon localization system for determining the location of hostile weapon fire. In one embodiment, the weapon localization system includes acoustical detection means for detecting energy of a first frequency originating from said hostile weapon fire; and for transmitting a first set of data describing the location of said hostile weapon fire; optical detection means for detecting energy of a second frequency originating from said hostile weapon fire, and for transmitting a second set of data describing the location of said hostile weapon fire; and processing means coupled to said acoustical and said optical detection means for receiving said first and said second set of data and for determining whether said location of said first set of data match said location of second set of data and for generating a signal output if said match occurs.

Abstract: The invention integrates an amplifier directly into an electromechanical transducer assembly. In one embodiment of this invention, power from a power supply is supplied to what can be described as an electromechanical amplifier that includes bridge circuits that directly drive the transducer elements. Each transducer element can include its own co-located switching network, such as, for example, a bridge circuit, that can be used with other system components to control when and for how long a voltage of equal magnitude and of either a positive or negative polarity is selectively directed to the element to expand or contract it in relation to a signal desired to be acoustically transmitted. Besides permitting an output of two voltages of equal magnitude and opposite polarity, the bridge circuit also permits an output that is “open” and one that allows a dissipation of transducer element charge.

Abstract: A synthetic-antenna side sonar device. Two transmission transducers which operate in interferrometric mode are fixed to the two ends of a physical antenna of a sonar. The forward speed of the sonar is chosen so that the zeros of the physical reception antenna coincide with one out of two of the side lobes of the radiation diagram of the synthetic antenna. Also the speed is chosen so that the zeros of the physical diagram of the interferrometric transmission antenna coincide with the other side lobes. This arrangement increases the range and thus the hourly coverage of a sonar for a given speed.

Abstract: Disclosed is a three-dimensional radar apparatus comprising a radar transmitting/receiving unit, a three-dimensional polygon-generating unit, and a three-dimensional graphics unit, wherein a radar transmitter/receiver outputs signals concerning orientation information, distance information, and reception intensity information on the basis of a radio wave reflected from a target, and a scan converter is used to convert the signals concerning the orientation information, the distance information, and the reception intensity information into two-dimensional radar image data composed of two-dimensional rectangular coordinates and brightness information of each of picture elements. The two-dimensional radar image data is also inputted into the three-dimensional polygon-generating unit to perform polygon-generating processing on the basis of the two-dimensional rectangular coordinates and the brightness information of each of the picture elements.

Abstract: The proposed velocity-measuring device (1) can measure the velocity of a wide range of objects via simple sound waves utilising the Doppler-effect principle. The velocity-measuring device (1) consists of a base unit (10) with a command-display unit (17). The base unit (10) holds a sound wave emitter with no less than one loudspeaker (8), a sound wave receiver with no less than one microphone (9), a computing unit and a display screen. In order to measure velocities the device (1) shall be placed next to the projected object line of movement in such a way that the sound waves and the line of movement meet at an acute or obtuse angle. The sound waves striking the followed object shall be partially reflected and subsequently received by the microphone (9) of the receiver. The difference between the emitting frequency and the echo frequency shall be analysed within the computing unit, producing the object velocity. The calculated velocity shall be shown via the control-display unit (17).

Abstract: The invention relates to a method of screening an acoustic signal or a spectrum line of maximum energy transmitted by a “target” that can be submerged at sea, from among a multitude of acoustic signals coming from any noise generators radiating acoustic signals of the same type with higher energy than energy E, employing, for example, (1) a set of N submersible acoustic pickups identically parameterized in surveillance mode, designed to detect the presence of the signal or a desired spectrum line, with the set of N pickups defining any number of surveillance cells with two adjacent pickups, each pickup being associated with one or more target detection regions defined as the geographic areas within which the presence of the “target” is deemed detectable and outside which the “target” is deemed nondetectable, and (2) a maximum number Nmax of pickups relating to one or more “special” areas (selected from a set of elementary geographic areas) of a given surveillanc

Abstract: A compact self contained portable, buoyant, water depth and temperature recording device. Allowing the user to gather depth recordings for safety and sporting situations. With it's simplicity of use, portability, and minimal storability factors , makes the units capabilities of use extend beyond the present large and permanent mounted counterparts.

Abstract: Spatial-temporal waveform diversity methods vary or modulate the far-field radiated waveform of a radar and/or communication antenna as a function of look direction (sidelobe structure). Radar detection performance and angle of arrival estimation are enhanced to deny a coherent reference to non-cooperative bistatic radars and coherent repeater jammer systems. In the most general case, the spatial-temporal modulated waveform varies as a function of angle, based upon the principles of multi-dimensional Fourier synthesis. Spatial-temporal denial is achieved with as few as two auxiliary antennas bracketing a main antenna. The same methods for spatial-temporal waveform diversity can also embed communications signals into the transmitted radar waveform for one-way simulcast of both waveform types. These same directionally dependent simulcast waveforms can incorporate navigation signals for enhanced precision engagement.

Abstract: An interactive data analysis system is disclosed that utilizes interactive graphic techniques to analyze ocean properties of a region of interest. The interactive system allows for a user to edit observed ocean data based on his/her a priori knowledge and insight so as to derive accurate ocean profile data.

Abstract: A bulk, quasi-periodic phase-matched difference-frequency (DFG) process in field-poled LiNbO3 bulk crystal permits continuous tunability of the output radiation in the 3.0-4.1 &mgr;m wavelength range through grating rotation. DFG in QPM-LiNbO3 crystal, carried out using a Nd:YAG laser and a high power semiconductor laser at the quasi-phased matching (QPM) degeneracy point, results in an ultra wide 0.5 &mgr;m acceptance bandwidth, permitting crystal rotation-free wavelength tuning of 4.0-4.5 &mgr;m, with 0.2 mW output power at 4.5 &mgr;m.

Abstract: A support member preferably made of a metal such as cold rolled steel is disposed in a looped configuration and is provided with a gap. A transducer member preferably made of a piezoelectric material such as a ceramic is disposed within the support member. The transducer member is provided with a gap at a position corresponding to the gap in the support member. A closure member made from a suitable springlike material such as an alloy steel is attached to the opposite ends of the support member at the position of the gap as by welding. The closure member extends in a U-shaped configuration into the looped configuration (in section) defined by the support member and the ceramic member. The axial length of the closure member defines the bandwidth of the frequency vibrations generated by the transducer member.