Abstract: A method and a device for detecting fodder waste/loss within a fish enclosure (1), where a sound transmitter (4) and a hydrophone (6) are disposed as an upwardly directed echo sounder close to the bottom of the enclosure (1). Sound echoes from objects situated above the sound transmitter (4), are picked up by the hydrophone (6). A measuring unit (8) separates signals from the hydrophone (6) into various frequency bands close to the transmitted sound frequency. The distance and amount of the objects are determined in a way similar to the one used in echo sounders. Sinking objects will cause rejected sounds having frequencies slightly higher than the transmitted frequency, so called Doppler effect, and the frequency difference is a measure of the sinking speed of the object.

Abstract: A phase difference measuring apparatus obtains a first receive signal by transmitting and receiving a to-be-measured material in a reference state and a second receive signal by transmitting and receiving a signal wave to and from that material in a measured state. The apparatus finds a reference phase difference .theta..sub.1 from the transmit wave and first receive signal and an apparent phase difference .theta..sub.2 ' from the transmit wave and second receive signal. The apparatus adds the apparent phase difference .theta..sub.2 ' to a product of the number of rotations, n, the apparent phase difference .theta..sub.2 ' passes through a given reference point and an angle of 360.degree. to find a true phase difference .theta..sub.2. The apparatus varies the number of rotations, n, to n+1 when the apparent phase difference .theta..sub.2 ', while being increased, passes through the reference point and that number of rotations, n, to n=n-1 when the apparent phase difference .theta..sub.

Abstract: A Doppler shift detector for determining the Doppler shift between a transmit signal and a receive signal uses clocked delay lines. The clocked delay lines count the number of edges in an applied signal thereto (e.g. the receive signal) at various positions in the delay line in accordance with a clock signal. Period detection logic ascertains the mean position of counted edges and thence the period of the applied signal. The Doppler shift is then calculated from the measured periods of the transmit signal and receive signal. The delay line for the receive signal is clocked by either the receive signal itself or the transmit signal.

Abstract: A method and apparatus for preventing the occurrence of range ambiguities and Doppler ambiguities in both a radar and sonar environment. A series of N pulses are produced, each of which contains a number of contagious subpulses. Each of the subpulses exhibit a different frequency than the remaining subpulses in that particular pulse. Furthermore, the order of appearance of the subpulses in each of the pulses is unique with respect to the remaining pulses in the series. A matched filter receiver and Doppler processor are used to provide auto correlations and cross correlations to prevent the range ambiguities and Doppler ambiguities.

Abstract: Groundwater velocity and direction of flow are determined by insertion into borehole below the water table of a sound source and a plurality of sound sensors. A periodic sound signal is emitted by the sound source, which is submerged in groundwater at the bottom of the borehole. The sound signals are sensed by the sound sensors, which are also submerged in the water in the vicinity of the sound source. Owing to the Doppler effect, there is a shift in the frequency of the sound signals observed by the different sound sensors. The differences in frequency are determined by pulse counters and used to compute the components of groundwater velocity along north-south and east-west axes. The velocity of groundwater flow and its direction are determined by vector addition of the groundwater velocity components. These computational processes are carried out by an appropriately programmed microprocessor.

Abstract: A phase difference measuring apparatus obtains a first receive signal by transmitting and receiving a to-be-measured material in a reference state and a second receive signal by transmitting and receiving a signal wave to and from that material in a measured state. The apparatus finds a reference phase difference .theta..sub.1 from the transmit wave and first receive signal and an apparent phase difference .theta..sub.2 ' from the transmit wave and second receive signal. The apparatus adds the apparent phase difference .theta..sub.2 ' to a product of the number of rotations, n, the apparent phase difference .theta..sub.2 ' passes through a given reference point and an angle of 360.degree. to find a true phase difference .theta..sub.2. The apparatus varies the number of rotations, n, to n+1 when the apparent phase difference .theta..sub.2 ', while being increased, passes through the reference point and that number of rotations, n, to n=n-1 when the apparent phase difference .theta..sub.

Abstract: A sonar antenna with transducers symmetrically distributed along an axis (fore/aft axis) and a perpendicular axis (starboard/port axis) in a plane on a circular base. Placement and polarities of the transducers, along with a phase and sequence of feeding two distinct frequencies to the transducers create four emission lobes inclined at 30 degrees one emission lobe with respect to each axis. Summation of reception signals (echos) from selected transducers based on frequency and accounting for time allow for the determination of fore/aft and starboard/port reception signals from which a velocity of the antenna or a vehicle attached to the antenna can be calculated.

Abstract: The signal appearing at the receiver input of a pulse code active sonar dng a return echo period, is sampled, time compressed and stored in a memory. The time compressed sample is successive read-out of memory, with each individual "read-out" hetrodyned with a discretely different doppler compensation frequency signal. The successively processed read-outs are passed through an "on line" correlation detection device to determine presence of a correctly compensated pulse code echo.

Abstract: A system and method for measuring current velocities using coded-pulse broadband acoustic signals. Autocorrelation of two phase coded pulses which are in the water during a single transmission cycle is used to calculate a Doppler frequency. The effective result is current profilers having improved profiling range and spatio-temporal resolution.

Abstract: The present invention is directed to provide an underwater detection system which can determine frequency components contained in echoes arriving from all azimuthal directions at high speed and enhance target discriminating capabilities by presenting such frequency components.The underwater detection system rotates a pair of ultrasonic receiving beams having a fixed phase angle difference, measures phase differences between two signals picked up by both ultrasonic receiving beams, determines carrier frequencies contained in target echoes from the phase differences, derives magnitudes and directions of moving velocities of targets from the carrier frequencies, and displays such target data in different colors. Furthermore, it provides such information as over-the-ground velocities of targets themselves upon compensating target velocity data with ship velocity data.

Abstract: A method of remotely determining the three-dimensional velocity of a fluid such as air or water, the method consisting in emitting signals of determined frequencies in at least three different directions by means of a plane array of transducers, and in using said transducers to pick up acoustic signals backscattered by the fluid, the method consisting in emitting trains of signals at different determined frequencies f1, f2, and f3, firstly in a determined direction D1, then in a determined direction D2, and finally in a determined direction D3, and subsequently in picking up all of the signals backscattered by the fluid. The invention makes it possible to improve the accuracy and to increase the maximum range of measurements.

Abstract: A sound detection and ranging (SODAR) system for taking wind measurements by sending out acoustic pulses and then measuring acoustic energy reflected back to the instrument by the atmosphere. The acoustic pulses are formed using digital beamforming technology which allows the acoustic pulses to be steered independent of frequency due to a time delay design. Also, the present invention SODAR instrument allows wideband capability that is limited only by the dimensions of the antenna array. Furthermore, the present invention SODAR instrument allows the acoustic pulses to be variably steered and allows multiple acoustic beams to be simultaneously received.

Abstract: A signal processing system for determining sea floor composition based on the frequency waveform and Doppler shift transmitted from an acoustic penetrometer includes a hydrophone for receiving the penetrometer waveform. The hydrophone output is digitized and passed to a general purpose computer where it is analyzed by a signal processing program. The signal processing program performs various signal transformations to increase the quality of the input waveform and isolates a penetration event. Additionally, the input signal is converted to an equivalent velocity waveform. A curve fitting algorithm is then used to determine the points within the velocity waveform that mark the initiation and termination of the penetration event that corresponds to the impact of the penetrometer with the sea floor. Once the initiation and termination of the penetration event are known, the velocity waveform is numerically integrated between those two points.

Abstract: A Doppler-effect speed detecting apparatus for detecting a ground speed of a motor vehicle, including a transmitter, a receiver for receiving a portion of a wave transmitted by the transmitter and reflected by a road surface, a circuit for detecting an output level of the receiver, and a ground-speed determining device for determining the vehicle ground speed, on the basis of the frequencies of the transmitted and received waves, according to a predetermined first rule when the output level of said receiver is higher than a predetermined threshold value, and according to a predetermined second rule different from the first rule when the output level is not higher than the threshold value.

Abstract: A triangulation method and apparatus for measuring the velocity of a flowing material at a point of interest along two lines of sight which have different vector components. The flow velocity along two different image vectors is measured simultaneously by separately processing the signals from left and right reception apertures (14, 16). In one case, the positions of the reception apertures are held constant and conventional dynamic focussing on receive is used to steer the apertures to follow the transmitted energy as a function of range depth. In an alternative case, the transducers included in each reception aperture are dynamically reassigned in order to maintain a fixed triangulation angle. In this case a reception aperture shifts away from the transmission aperture (12) to track the received backscattered ultrasonic energy at a constant triangulation angle.

Abstract: An underwater detection system which searches the water in a wide range of directions and displays moving targets in different colors depending on speeds of the targets comprises an ultrasonic transmitting unit (101) for radiating a search pulse having a carrier frequency in a wide range of directions, an ultrasonic receiving unit (1p, 1q) for successively searching areas in mutually different directions in the wide range of directions to receive ultrasonic signals coming from each of respective directions therein at least two times, a phase difference detector (10, 12), detecting a phase difference between the carriers of the reception signals having come from the same direction in the wide range of directions and caught by the ultrasonic receiving unit, a calculator (18 calculating the angular frequency of the reception signals based on the phase difference of the carriers of signals, a color signal generator (103), producing predetermined color signals corresponding to angular frequencies based on signals

Abstract: In a correlation device, a system and method for measuring velocities using a single coded pulse generator. The correlation device may also include maximum likelihood estimation techniques for processing the echo signals received from a plurality of transducers. The presently preferred embodiment of the device is as a current profiler having a bottom tracking capability for providing vessel velocity.

Abstract: An ultrasonic digitizer pen includes an ultrasonic transmitter to transmit ultrasonic waves through the air, to illuminate a writing surface. An ultrasonic receiver receives the waves reflected off the illuminated writing surface. The writing surface is a mouse pad, a wooden tabletop or other surface having a natural amount of roughness to reflect ultrasonic waves in all directions.The transmitter and receiver are located in the pen near its tip and have radiation patterns pointing generally in the same direction, and parallel to the writing surface. At least one of the radiation patterns is narrow in a horizontal plane and wide in a vertical plane, to illuminate a narrow area of the writing surface.phase measuring circuit measures the phase difference between the transmitted and the received ultrasonic signals. This phase is indicative of the displacement of the digitizer pen.

Abstract: A system measures the velocity of a moving body such as a ship and a water body. The system uses a first apparatus which measures the speed of a moving body by detecting a phase difference between a reference signal and echo signals resulting from a transmitted ultrasonic signal, implementing a Fourier transformation on the phase difference data obtained, computing the speed of the ship with respect to the water based on the Fourier spectrum data, and, computing the velocity of a water current based on the speed of the ship with respect to the ground and the speed of the ship with respect to the water obtained.

Abstract: The proposed method permits expansion, compression or reversion of a frequency of a Doppler shift signal. Shift frequency components of a measured Doppler shift signal are multiplied desired times so as to eliminate aliasing or permit precise detection of slow targets. A phase difference obtained at a time in a very short period is substituted with a phase difference obtained in a period longer than the very short period. The frequency conversion is applicable to the continuous wave Doppler system and the pulsed Doppler system.

Abstract: A system and method for measuring current velocities using coded-pulse broadband acoustic signals. Autocorrelation of two phase coded pulses which are in the water during a single transmission cycle is used to calculate a Doppler frequency. The effective result is current profilers having improved profiling range and spatio-temporal resolution.

Abstract: A continuous wave driven ultrasonic transducer for determining doppler frequency shift in reflected ultrasonic pressure waves in which the transmitter and receiver sections are constructed of a composite core having a plurality of segments of piezoelectric material separated by acoustic suppression material. Also disclosed is a method of reducing acoustic and mechanical cross coupling between piezoelectric transmitter and receiver sections of an ultrasonic transducer by arranging segments of piezoelectric material in a lateral array, and separating the piezoelectric segments with ultrasonic acoustic suppression material to produce a composite transducer core of reduced acoustic and mechanical cross coupling.

Abstract: An apparatus and method for measuring the frequencies of a pair of signals simultaneously present in a composite signal, comprising the steps of includes components for squaring the composite signal, filtering the squared signal for separating a first pass band and a higher frequency second pass band, instantaneously measuring the frequencies of the first and second pass bands and determining the individual frequencies of the pair of signals from the measured frequencies of the first and second pass bands.

Abstract: The invention relates to a device and process which utilize the Doppler effect for measurement of the performance of blasting operations, in particular to the measurement of face velocity. The measuring device comprises radiation generating and receiving means and a signal analyzing means.

Abstract: A flow meter for detecting the average speed of an object in such a manner that an ultrasonic pulsed continuous wave is repeatedly transmitted toward the object to obtain a phase vector from the reception signal of the wave reflected from the object, the phase difference between consecutive ones of phase vectors obtained at an interval T equal to the period of transmitted wave is detected, a plurality of phase difference values are added and averaged to obtain an average phase difference value, and a Doppler frequency is calculated from the average phase difference value to obtain the average speed of the object, in which in order to remove an error caused by aliasing of an angle in the course of the arithmetic operation for obtaining the average phase difference value, a plurality of presumed average phase difference values having the error are calculated from the average phase difference value, the difference between the change of a phase caused by adding the phase difference values successively and the cha

Abstract: The velocity of a vessel is determined in real time by a doppler sonar sym providing acoustic beams wherein received beams provide a plurality of bins or returns from various depth segments. The frequency shift with respect to at least two different bins is determined. The velocity of the vessel with respect to each bin is determined according to the phase shift of the respective bin. The vessel velocity is determined as an average of the determined velocities of the bins along the acoustic beam. The acoustic beams are paired to form beam pairs wherein each bin in one beam of the beam pair has a corresponding bin in the other beam of the beam pair. The phase shifts of the corresponding bins are used to determine a relative frequency shift for the corresponding bins. This determination is made along the length of the beams of the beam pair and averaged. The averaged resolved ship doppler profiler velocity when compared to inertial velocities determines water current velocities.

Abstract: A technique for obtaining a class of beam patterns is described which results in eliminating the Doppler spread effect of the mean transverse component of flow of scatterers. This is accomplished by weighting various array elements. This component of flow is typically the main contributor to Doppler frequency spread. With this component eliminated, the other contributor of Doppler spread is due to the turbulent or fluctuating scatterer motion on the scale of the scattering volume. This contributor is smaller of the two and is estimated by standard Doppler methods.

Abstract: An apparatus for measuring the velocity distribution in a fluid by a pulse-Doppler method using an ultrasonic waver or an electromagnetic wave. The observation wave is transmitted to and received from the fluid and the reflected echo from the fluid is received so as to obtain the Doppler frequency. A predetermined transverse section is scanned with the observation wave so as to obtain the Doppler velocity distribution in the transverse section. Since the Doppler velocity distribution only contains the component in the direction of the observation wave, the Doppler velocity distribution is cumulatively integrated in the direction orthogonal to the direction of the observation wave and the integrated values are differentiated again in the direction of the observation wave, thereby obtaining the component in the orthogonal direction by calculation. If the observation wave is an ultrasonic beam, it is possible to observe the velocity distribution of the bloodstream in the heart.

Abstract: An ultrasonic ground speed sensor has a single transducer which both transmits and receives ultrasonic signals. The sensor is mounted on a vehicle in alignment with the direction of the vehicle, the transducer having a built-in angle with the body of the sensor unit. The transmitted signal is clocked by a 16 MHz clock, with the signal received by the transducer selectively filtered and amplified. A temperature sensor is also used to determine the speed of the transmitted and received signal. A 64-cycle sample period is used, as well as multiple counters and a signal processor to increase accuracy and minimize erroneous readings. A drop-out detector and monitoring system sensor is also described. The vehicle speed is calculated from a Doppler-based formula as a function of both the sum and difference of the transmitted and received signal frequencies. Also disclosed is a gasket seal having leak holes for drainage from the interior of the sensor.

Abstract: A speedometer is provided for determining speed by providing a sound signal at a first frequency, receiving a second signal which is the reflection of the first signal, and determining difference in frequency between the first and second signals created by the Doppler Effect. A speech synthesis chip within the speedometer provides a verbal indication of velocity. In this way, a person using the provided speedometer does not have to look at a dial or other visual indicator.Provided within the speedometer is a heat-sensitive transducer for measuring the air temperature. In this way, the speedometer can take into account the change in the speed of sound with respect to temperature when calculating velocity.

Abstract: A flow meter, in which pulsed continuous ultrasonic wave is transmitted towards an object at predetermined intervals T to obtain a phase vector from a reception signal of wave reflected by the object and which calculates a Doppler frequency from the average value of phase differences between phase vectors at the sampling interval T to obtain a signal indicating the speed of the object, comprising a phase difference calculator by the auto-correlation method, by which a plurality of phase difference vectors indicating phase differences between phase vectors are added, the argument of the sum vector thus obtained representing the average phase difference, or a phase difference calculator by the 2-axial-component method, by which a phase difference is divided into 2 axial components, a cosine value and a sine value, and the average phase difference is obtained by using the average value for each of the components, and a phase difference calculator by the phase difference averaging calculator, by which a plurality

Abstract: A well logging system which monitors the flow rate of a fluid flowing in a borehole traversing an earth formation includes a sonde. A transmitter located in the sonde transmits acoustical waves into the fluid at a predetermined frequency. A receiver also located in the sonde receives reflected acoustical waves. The receiver also provides a signal corresponding to the received reflected acoustical waves. The provided signal is processed for being sent uphole by way of a cable. Electronics at the surface include circuitry which derives the velocity of the fluid in accordance with the frequency of the processed signal and the predetermined frequency. The circuitry provides an output signal corresponding to the derived velocity of the fluid flowing the borehole.

Abstract: An electrical circuit to detect frequency domain information from ultrasonic signals that have been doppler shifted by motion of an object in the field of the ultrasonic beam. The circuit receives the doppler shifted signal, creates separate upper and lower sideband signals and compares the signals to a threshold level to produce digital transition pulses. The transmitter pulses are digitized to form pulses of uniform width and amplitude, whose frequency can be correlated to the object motion.

Abstract: An automatic, ultrasonic system for controlling the filling of different sizes of beverage containers which may or may not contain various quantities of ice. The system includes a transducer assembly and a control module, both preferably connected to a beverage dispenser valve assembly. The transducer assembly includes at least two piezo-electric crystals for separately transmitting and receiving ultrasonic wave energy from the grate, the cup lip, the top of any ice in the cup, and the rising liquid level, and for generating signals corresponding to the travel time of the ultrasonic energy. The control module includes a microcomputer and associated circuitry. The system can include two separate transmitter and receiver crystals, or in a preferred embodiment two transmitter-receiver pairs of crystals.

Abstract: A method and device are provided for the automatic recognition of targets from "Doppler" echoes. The method consists in comparing sequentially the spectra of the "Doppler" signal retransmitted by each target with successions of spectra corresponding to known targets stored in a dictionary memory and indicating the type of target when the spectra of the signal retransmitted by the target have been recognized.

Abstract: A measure window (29-30, FIG. 2d) is provided in a Doppler velocity profile (FIG. 2c) by deleting an initial section (T.sub.1) and a terminal section (T.sub.2) of each emission cycle of a train of ultrasound of a period T so as to conserve only the section (T.sub.o) which it is desirable to study. The conserved section (T.sub.o) is thereafter segmented into a certain number (N) of measure channels. The advantage of restricting the zone divided into channels to the part which is really useful is that the definition of the profile which is obtained is improved, even when the emitter-receptor of ultrasound is located at a relatively important distance in comparison with the depth of the zone which is studied.

Abstract: The present invention concerns a process for removing all ambiguity from the measurement by the Doppler effect of the speed of a target. It consists in obtaining a signal of Doppler shift relating to a series of ultrasonic pulses sent in the direction of the target and received after their reflection onto this target, the recurrence frequency of the pulses constituting an ambiguity limit of these speed measurements, wherein the measured Doppler shift is transposed by modulating the signal received by a signal at a frequency called determination frequency, so as to bring from a known value the spectral components to be analyzed in the useful measuring band and after measuring the true speed values are worked out by adjunction of a correction that depends upon the determination frequency that is used, this process being applicable to measuring the speed of blood in the medical field.

Abstract: An ultrasonic wave signal having its frequency varied continuously is transmitted from an ultrasonic wave transmitter toward a moving body. The wave reflected from the moving body is received by an ultrasonic wave receiver, and the resulting signal is frequency-demodulated to obtain a signal representing a frequency variation. A signal representing the feature of the moving body is produced with use of a signal representing the frequency variation of the transmitted ultrasonic wave and the signal representing the frequency variation of the received ultrasonic wave.

Abstract: The sampling volume of a pulsed Doppler system is increased to a length greater than that corresponding to one pulse by sampling the reflections of each launched pulse a plurality of successive times and accumulating the samples.

Abstract: A speed detecting device comprises a comparing circuit for comparing the amplitude of a Doppler signal with a reference amplitude value, and an excluding circuit for excluding a speed signal corresponding to the Doppler signal of the amplitude smaller than the reference amplitude value, whereby the speed signal corresponding to the Doppler signal of the amplitude larger than a predetermined value.One embodiment of the device further comprises a circuit for selecting and outputting a Doppler signal of the largest amplitude, thereby detecting a vehicle speed based on the Doppler signal of the largest amplitude.

Abstract: Continuous wave (CW) Doppler imaging employs a linear array of transducer elements with a first plurality of elements functioning as an ultrasonic wave transmitter and a second plurality of elements functioning as a receiver of the reflected ultrasonic wave. Time delay circuitry connected to the transmitter and receiver elements define the beam focus and beam steering of the ultrasonic wave.

Abstract: Apparatus for measuring windspeed and/or direction with the aid of a sound-wave transmitter (25) and a receiver (25) for receiving reflected sound waves, in which apparatus the sound waves (25a) are transmitted in a multiplicity of directions, and in which a compilation of the measuring result obtained with each measuring operation gives a measure of the speed and/or direction of the wind. The transmitter and/or the receiver (25) are arranged to rotate, so that measuring results from a plurality of measuring locations can be evaluated. The transmission lobe (25a) is inclined in relation to the axis of rotation of the transmitter and/or receiver.

Abstract: The invention concerns a method and apparatus for detecting Doppler-shifted waveforms in electrical signals. A replica is derived from the waveform prior to Doppler shift and stored in a storage device as a non-uniform profile having progressively increasing distortion along its length. The replica storage device is connected non-uniformly to correlating means such that the correlated replica profile has a degree of uniform distortion varying with storage position simulating varying degrees of Doppler shift. The electrical signal is uniformly correlated with the replica while the replica storage position is varied. An output signal is generated indicating correlation variation. The electrical signal is repetitively sampled and a maximum correlation is detected when the waveform occurs in the electrical signal with a degree of Doppler shift matching that simmulated by the correlated replica. The invention also includes apparatus for performing the method.

Abstract: This invention is directed to improved pseudorandom noise velocimeters and methods therefor, using the Doppler effect, to enable the external measurement of the speed of a moving target within a fixed conveying medium. In accordance with a preferred embodiment of the present invention a continuous pseudorandom ultrasonic noise signal formed by a repetitive code C having n different elementary segments S is radiated. Correlation between a received echo and the delayed radiated signal is accomplished by proceeding successively for each elementary segment, using a different measuring band, for a period corresponding to the period of each segment. The correlation values thus obtained are then stored and thereafter a Doppler low frequency curve is reconstituted by regrouping the correlation values corresponding to the different elementary segments of the repetitive code.

Abstract: There is described a digital sonar receiver having a novel beamformer, own doppler nullifier (O.D.N.), and adaptive time varied gain controller. The beamformer interrogates a multi-element transducer by utilizing an interleaved sampling scheme which samples the elements in the transducers array sequentially, in such a fashion that continuous, uniformly spaced samples are obtained. The samples are subsequently converted into digital format, weighed and summed. The O.D.N. eliminates the own ship's doppler effect on the beam output signal resulting in a half beam output signal representative of the target doppler. The O.D.N. offsets the frequency of the beam output signal and a digital generated signal representative of the own ship's doppler. The O.D.N. multiplies these two offsetted signals resulting in a signal lying in each of the sum and difference frequency bands for which the signal lying in the difference frequency band corresponds to the target doppler.

Abstract: 1.

Abstract: In a Doppler acoustic radar system, bistatic transmitting and receiving antennas are employed in a manner to significantly improve wind measurement performance, and to simplify equipment deployment.

Abstract: This method comprises laying onto the water bottom at least one line of acoustic transducers which are put in energized condition when an iceberg is approaching the location of this line. Acoustic signals are then sequentially transmitted from at least one of said transducers, some of them being reflected by the underwater part of the iceberg and sensed by acoustic receivers located on both sides of the transmitter on the transducer line. The outline of the underwater portion of the iceberg and its draught are determined by automatically drawing the geometrical envelopes of a system of ellipsoids whose foci are the transmitter and the different receivers.

Abstract: A system for remote measurement of wind velocity and direction. An acoustic echo transmitter for directing a beam of acoustic energy toward a zone, and a plurality of receivers for receiving acoustic energy scattered by wind in the zone, with each receiver output having a doppler frequency component. A system which permits positioning the receivers at various elevations and various distances and angles from the transmitter, and a system particularly sensitive to measurement of vertical wind velocity.

Abstract: A system and method for measuring current velocities using coded-pulse broadband acoustic signals. Autocorrelation of two phase coded pulses which are in the water during a single transmission cycle is used to calculate a Doppler frequency. The effective result is current profilers having improved profiling range and spatio-temporal resolution.