Abstract: A hybrid serial/parallel bus interface has a data block demultiplexing device. The data block demultiplexing device has an input configured to receive a data block and demultiplexes the data block into a plurality of nibbles. For each nibble, a parallel to serial converter converts the nibble into serial data. A line transfers each nibble's serial data. A serial to parallel converter converts each nibble's serial data to recover that nibble. A data block reconstruction device combines the recovered nibbles into the data block. The data block is employed by a gain controller. Each nibble has at least two start bits whose states collectively represent both a function and/or destination.

Abstract: An amplifier circuit to amplify a sequence of echoes and to generate a corresponding sequence of amplified signals. In an embodiment, the amplifier includes an operational amplifier, with variable input and feedback resistances such that the ratio of the two resistances can be controlled. A gain control block controls the ratio in a time dependent manner to obtain desired gain factors for each of the echoes. The gain factors can be pre-computed such that all the echoes are gained to the same level in case of an ultra-sound system.

Abstract: Detecting an object using sound waves includes outputting a sound wave from a transducer, receiving an echo after outputting the sound wave, obtaining a threshold value based on the echo and plural other echoes that are within a predetermined range of the echo, and determining if the echo is a result of the sound wave based on the threshold value.

Abstract: The present application discloses a method of and an apparatus for measuring a distance using an ultrasonic wave. The method of measuring a distance using an ultrasonic wave includes the steps of receiving through an ultrasonic sensor a signal from an ultrasonic transmitter; amplifying the received signal; filtering a high-frequency component from the amplified signal, thereby generating a filtered signal; generating an output signal when the filtered signal satisfies a predetermined condition; and computing a distance based on a period of the output signal.

Abstract: Each of plural detection units performs a signal transmission-reception operation responding to at least one of a plurality of kinds of operation timing signals repeated at a predetermined periodicity. The number of continuous reception times of the reflection signal is counted and used to determine obstacle detection when the number of counts is larger than or equal to a predetermined value. The transmission-reception operations are controlled by an operation timing signal having a periodicity shorter than the predetermined periodicity.

Abstract: The initial detection of a signal of interest in a data stream involves transmitting a signal received by a sonar or a radar to signal detection equipment wherein a signal of interest is characterized by a state model x(t) with values in a finite set {x1, . . . , xN}, to which there corresponds a finite set {?1, . . . , ?N} of N values of an observation variable ?, characteristic of this signal. To detect the signal of interest a detection criterion ?n(t) is simultaneously calculated in two different ways. The larger of the two calculated values is assigned to the criterion of ?n(t) which is then compared with a detection threshold.

Abstract: An obstacle detection system has multiple ultrasonic sonars. When a threshold value used for determining an existence of an obstacle is compared with a receiving signal having been amplified at a predetermined gain, the sonar having a receiving mode is provided with the gain which is higher than that of the sonar having a sending/receiving mode. Thus, the sensitivity of the sonar having the receiving mode can be improved so that a continuous sound field of the sonar is broadened. Accordingly, the distance of the border of the continuous sound field of the obstacle detection system from the vehicle can become substantially even.

Abstract: A method and a device for monitoring a space for the presence of a foreign body comprises at least one transmitter and a first and second receiving device. The signal of the second receiving device which is spaced further apart from the transmitter than the first receiving device is evaluated for its parasitic signal portions. If the distance between the first and the second receiving device is not too great, it can be assumed that parasitic signal portions detected in the second received signal are also contained in the first received signal. In this case, it is recommended to discontinue monitoring the space or to discard any result of this monitoring already obtained at least until no parasitic signal portions are detected in a repeated evaluation of the second received signal.

Abstract: The invention relates to an ultrasonic sensor with an adjustable detection range for use in gaseous media, preferably air. A threshold value generator generates threshold value curves that are fed to a comparator. The change in the detection range of the ultrasonic sensor, namely, the change in its switching point curve, is carried out by influencing the threshold value curves, whereby, in a selectable manner, the detection range can be adjusted either exclusively in the lateral extension of the sonic cone or else in the axial and lateral extensions of the sonic cone.

Abstract: A hybrid serial/parallel bus interface has a data block demultiplexing device. The data block demultiplexing device has an input configured to receive a data block and demultiplexes the data block into a plurality of nibbles. For each nibble, a parallel to serial converter converts the nibble into serial data. A line transfers each nibble's serial data. A serial to parallel converter converts each nibble's serial data to recover that nibble. A data block reconstruction device combines the recovered nibbles into the data block. The data block is employed by a gain controller.

Abstract: In an under water detection for detecting the phase difference of an echo by two reception beams according to a split beam method, the difference ?? between the phase difference of an echo detected by first and second reception beams formed in some direction and the phase difference of the echo detected by first and second reception beams which is formed in a direction rotated from the former direction concerned by a predetermined angle is detected by a phase detector. A reliability judging unit judges whether the difference ?? detected by the phase detector is within a predetermined range or not. If the difference ?? is within the predetermined range, an echo is displayed on a display unit. If the difference ?? is not within the predetermined range, the echo is displayed with a specific color tone or the echo is not displayed.

Abstract: An obstacle detection device includes a transmitting portion for sending ultrasonic wave, a plurality of receiving portions provided at different positions and receiving reflected waves of the ultrasonic wave, a plurality of envelope wave acquiring portions for acquiring envelope waves corresponding to the reflected waves, on the basis of the reflected waves received by the receiving portions, determining portions for determining a peak of each of the envelope waves, storing portions for storing a partial data of the each of the envelope waves, whose peak is determined by the determining portions, estimating portions for estimating a starting point of the each of the envelope waves by using the partial and location determining portions for determining a location of an obstacle on the basis of the starting point of the each of the envelope waves.

Abstract: A parking sensor apparatus and method to keep air brakes from interfering with the parking sensor apparatus allow the parking sensor apparatus to be used with vehicles that have air brakes. The ultrasonic components of air brake noise is detected, and the alarm is bypassed when air brake noise exists. This technique reduces false alarms on vehicles with air brakes and allows the parking sensor apparatus to be used on the vehicle.

Abstract: A fish finder includes a transducer that repeatedly transmits ultrasonic pulse signals downward into the water and receives signals from the water, a first signal generating unit that generates a first signal on the basis of a reception signal at an identical depth caused by signals transmitted at least twice, and an interference detecting unit that detects an occurrence of interference on the basis of plural first signals at different depths.

Abstract: Pulse-echo ranging system are used in level measurement applications for determining the distance to a target object by measuring how long after transmission of a pulse an echo pulse is received. An echo profile (17) is generated and then processed to determine the temporal position of the echo pulse on a temporal axis. Based on the fact that the peak portion and the trailing edge of the echo profile are susceptible to be affected by the measurement environment and the target object itself, the accuracy in determining the echo arrival time is increased, by the steps of fitting a branch of a parabola (19) to a selected portion of the leading edge (18) of the echo profile (17) and determining the temporal position of the fitted parabola (19) on the temporal axis.

Abstract: Detecting an object using sound waves includes outputting a sound wave from a transducer, receiving an echo after outputting the sound wave, obtaining a threshold value based on the echo and plural other echoes that are within a predetermined range of the echo, and determining if the echo is a result of the sound wave based on the threshold value.

Abstract: A fish finder includes a transducer that repeatedly transmits ultrasonic pulse signals downward into the water and receives signals from the water, a first signal generating unit that generates a first signal on the basis of a reception signal at an identical depth caused by signals transmitted at least twice, and an interference detecting unit that detects an occurrence of interference on the basis of plural first signals at different depths.

Abstract: A method and apparatus for controlling pulses in a pulse-echo level measurement or time-of-flight ranging system. The apparatus comprises a controller, a transducer, and an energy storage device. The energy storage device is operatively coupled to the transducer through a relay. The relay is enabled and disabled by the controller and in the disabled state the energy storage device is allowed to accumulate energy. The energy is stored in the energy storage at a variable voltage level. The controller includes a component for determining a voltage level corresponding to an acceptable confidence level for echo pulses. The controller includes another component for determining a voltage level an increased response time.

Abstract: The invention relates to an adaptive comparator circuit comprising a comparator with a threshold value input which receives a threshold voltage and a signal input which receives a voltage signal. The threshold value input is connected to one pole by means of a switch and connected to the other pole of a first voltage source by means of a capacitor. The threshold value input is also connected to the signal input of the comparator by means of a diode or a second voltage source. The switch is controlled by the control signal of a signal transmitter. When the switch is in a closed position, the capacitor is charged with the voltage of the first voltage source. When the switch is in an open position, the capacitor is discharged in such a way that the threshold voltage of the signal voltage is corrected at a given time interval.

Abstract: Dynamic tuning of a tunable filter within the receiver of a pulse-echo ranging system. A filter tuning module compares a transmit signal and a filtered signal to obtain a phase difference indicative of any mis-match between the resonant frequency of the tunable filter and the transmit frequency. The filter tuning module outputs a phase correction signal corresponding to the phase difference and a controller uses the phase correction signal to determine any adjustments necessary to minimize the phase difference. Adjustments to the tunable filter may be made with each ‘shot’ or transmission.

Abstract: The adaptive system and method for ultrasound sensing comprises re-evaluating over time the detection threshold for predetermined sensing positions along the scanning direction to cope for the static target and environment changes at the sensing positions. The method includes comparing the measured echo value at each sensing position to a reference echo value corresponding to the same sensing position, and to iteratively determine a new reference value whenever the echo value is greater than the reference echo value and that the difference between the measured echo value and the reference echo value is lower than a detection assurance factor. The use of the adaptive ultrasound sensing system and method allows locating the sensor at different location without requiring a new calibration thereof, since the sensor learns the clutter dynamically and the detection thresholds are being built accordingly without being dependent on the environment in which the sensor is located.

Abstract: A time measurement system for measuring the delay between first and second signals comprises means for detecting the times of upcrossings when the first signal crosses a predetermined level (preferably substantially different from the average level) with a positive slope and the times of downcrossings when the first signal crosses the predetermined level with a negative slope. These events are transmitted to a remote device receiving the second signal, which uses the events to define respective staggered segments of the second signal, to sum said segments and to detect a predetermined feature in said sum, the position of said feature representing the delay between the first and second signals.

Abstract: A method and system for high-pass filtering to remove DC and/or low frequency components of a receive signal from the transducer of a level measurement system. In one embodiment, the method includes generating a maximum signal profile and a minimum signal profile for the receive signal, generating a midpoint reference signal from the maximum and minimum signal profiles and subtracting the midpoint reference signal from the receive signal to produce a filtered signal.

Abstract: A pulse-echo sonar scanner for a mobile robot includes a transmitter which generates a pulse signal, an acoustic transducer which transmits and receives acoustic signals, a receiver, means for determining performance characteristics of the transducer for a given pulse, means for storing the performance characteristics, and means for determining threshold levels for an echo based on the stored performance characteristics.

Abstract: The invention is directed to a system and method for detecting defects in a manufactured object. These defects may include flaws, delaminations, voids, fractures, fissures, or cracks, among others. The system utilizes an ultrasound measurement system, a signal analyzer and an expected result. The signal analyzer compares the signal from the measurement system to the expected result. The analysis may detect a defect or measure an attribute of the manufactured object. Further, the analysis may be displayed or represented. In addition, the expected result may be generated from a model such as a wave propagation model. One embodiment of the invention is a laser ultrasound detection system in which a laser is used to generate an ultrasonic signal. The signal analyzer compares the measured ultrasonic signal to an expected result. This expected result is generated from a wave propagation model. The analysis is then displayed on a monitor.

Abstract: The present invention relates to a system for using signals scattered by targets to determine position and velocity for each of the targets and comprises a set of transmitters and receivers of electromagnetic or acoustic signals, said transmitters and receivers dispersed to known points. Each pair of transmitter and receiver, monostatic or bistatic, is named a measuring facility. The ranges of the transmitters are chosen so that a target at an arbitrary point within the position space can be measured via scattering in the target by at least four measuring facilities. For each measuring facility, target detection occurs with constant false alarm rate in the form of probabilities over resolution cells with regards to range and Doppler velocity and conceivable targets are placed in a 2-dimensional linear space belonging to the measuring facility.

Abstract: A method and system for processing received sonar signals. The method and system generate bearing data signals based on the received sonar signal. The method and system continuously determine the signal strength of the received sonar signal and also continuously determine the total noise from the received sonar signal in the ocean environment in which the target is located. The method and system provide a sensor gain in response to the determined total noise and the signal strength, and adaptively calculate filter coefficients from the sensor gain and the determined total noise. The method and system also filter the generated bearing data signals using a filter having the calculated filter coefficients.

Abstract: The present invention separates noise from actual return echoes of ultrasonic sound waves generated by the transducer of a sonar type fish finder by comparing the timing of generated ultrasonic pulses and received signals and disregarding signals when such timing does not match.

Abstract: The present invention separates noise from actual return echoes of ultrasonic sound waves generated by the transducer of a sonar type fish finder by comparing the timing of generated ultrasonic pulses and received signals and disregarding signals when such timing does not match.

Abstract: The present invention provides an apparatus that automatically adjusts self-noise which apparatus can lower the lower limit value of a measurement range by reducing the effects of self-noise on measured values. This apparatus corrects self-noise when amplifying an output signal from a sensor 1 so as to conform to a sensor sensitivity G, further processing the amplified signal, and then outputting the processed signal as a measured value.

Abstract: The adaptive system and method for ultrasound sensing comprises re-evaluating over time the detection threshold for predetermined sensing positions along the scanning direction to cope for the static target and environment changes at the sensing positions. The method includes comparing the measured echo value at each sensing position to a reference echo value corresponding to the same sensing position, and to iteratively determine a new reference value whenever the echo value is greater than the reference echo value and that the difference between the measured echo value and the reference echo value is lower than a detection assurance factor. The use of the adaptive ultrasound sensing system and method allows locating the sensor at different location without requiring a new calibration thereof, since the sensor learns the clutter dynamically and the detection thresholds are being built accordingly without being dependent on the environment in which the sensor is located.

Abstract: A multiple dimension vector-based occupancy sensor. One or more sensors (for example, ultrasonic and/or infrared sensors) are used to produce one or more occupancy estimator vectors. The individual dimensions of the one or more occupancy estimator vectors are combined using a fusion based detection algorithm to produce a combined estimator signal. The combined estimator is then used to switch electrical loads when the combined estimator signal is above a predetermined threshold. The result is an occupancy sensor that has a very high probability of occupancy detection and a low probability of false tripping.

Abstract: A relative speed of an object is determined by monitoring random reflective surfaces in water. The system includes a first and second transmitter-receiver pair for producing echo signals of a monitored region. The monitoring pair of transducers are preferably positioned along an axis of motion of the object such that sampled data from the first and second transmitter-receiver pair are substantially similar but shifted in time due to a separation of transducers. Echo signal data from the transducers are then used to generate a time difference correlation function that is used to determine a time difference between the first and second signals. Based on the time difference between the time-shifted echo signals, a speed of a vessel is determined.

Abstract: A combined marine entertainment system and depth sounder (10) that more efficiently utilizes limited marine instrument panel space, that is more convenient and simple to operate, and that shares certain components and, therefore, is less expensive to manufacture and install. The apparatus includes a main unit (12) and a separate remote unit (14). The main unit includes a housing (16); an entertainment assembly including a display (20) and an entertainment component (18) positioned in the housing; and a depth sounder assembly including a depth display (48) positioned within the same housing as the entertainment assembly display and entertainment component.

Abstract: A method for estimating the curvature in a road is disclosed. The method measures an azimuth angle range and relative velocity between a host and a target vehicle, which determines whether a host vehicle is changing lanes or whether a target vehicle is changing lanes. The method calculates a heading angle of the host vehicle and calculates a corrected azimuth angle by adjusting the measured azimuth angle by the value of calculated heading angle. This method selects a curve that minimizes the mean square error between the curve and selected targets; and determines an equation that describes the curve, wherein the equation is used to predict the path head of the host vehicle.

Abstract: A method of detecting actual or incipient submersion of an electroacoustic transducer (2) facing downwardly toward a surface of fluent material to be sensed in a pulse-echo acoustic ranging system, the transducer having a skirt (6) surrounding a downwardly facing radiating surface (4) to maintain an air space (10) beneath the radiating surface even under submergence conditions, and the transducer being electrically energized to emit pulses of acoustic energy from the radiating surface, the system processing an electrical output received from the transducer following a pulse by repeatedly sampling it to obtain a response profile. Samples from an initial portion of the response of the transducer during a ring-down period following the transmit pulse are summed (FIG.

Abstract: A method of tracking an object comprising the steps of acquiring the position of at least one object; selecting the at least one object as a target; determining a sampling window which envelopes the target; obtaining an echo; repeating the foregoing step of obtaining an echo a predetermined number of times; determining valid echoes from the target; calculating the current position of the target from the received echoes; and repeating the steps of obtaining, repeating, determining, and calculating as desired. The step of obtaining an echo comprises the steps of transmitting a pulse at a desired frequency from a transducer; scanning for echoes within the sampling window by a receiver; and receiving at least one echo of the pulse at the receiver which are within the sampling window, the at least one echo having a frequency that matches the outgoing pulse frequency.

Abstract: A pulse-echo sonar scanner for a mobile robot includes a transmitter which generates a pulse signal, an acoustic transducer which transmits and receives acoustic signals, a receiver, means for determining performance characteristics of the transducer for a given pulse, means for storing the performance characteristics, and means for determining threshold levels for an echo based on the stored performance characteristics.

Abstract: A sonar depth sounder device and method for processing echo signals, reflected from objects within a body of water, utilizes a processor, a memory, a display, and a keypad connected to the processor. The receiver receives sonar signals indicative of ambient noise in an underwater environment. The processor receives an electrical signal representative of the ambient noise, and calculates a detection threshold. The detection threshold is calculated by multiplying a scaling factor times the variance of the signal indicative of the ambient noise, and adding that product to the mean of the signal indicative of the ambient noise in the underwater environment. A transmitter then excites a transducer which emits sonar pulses into a body of water, and a receiver receives reflected sonar echo signals. When the intensity of the reflected sonar echo signals is less than the detection threshold, the reflected echo signals are eliminated from processing.

Abstract: A sonar depth sounder device and method for processing echo signals, reflected from objects within a body of water, utilizes a processor, a memory, a display, and a keypad connected to the processor. The receiver receives sonar signals indicative of ambient noise in an underwater environment. The processor receives an electrical signal representative of the ambient noise, and calculates a detection threshold. The detection threshold is calculated by multiplying a scaling factor times the variance of the signal indicative of the ambient noise, and adding that product to the mean of the signal indicative of the ambient noise in the underwater environment. A transmitter then excites a transducer which emits sonar pulses into a body of water, and a receiver receives reflected sonar echo signals. When the intensity of the reflected sonar echo signals is less than the detection threshold, the reflected echo signals are eliminated from processing.

Abstract: The invention relates to an ultrasonic measuring apparatus for determining the geometrical position of a boundary between two materials in a first material from a reference place, more particularly for wall thickness or fault testing. To enable even very thin-walled materials to be measured, the measuring apparatus isolates the reflected ultrasonic signals from the ultrasonic mixed signal received by the receiver, which consists of the ultrasonic signal reflected at the boundary to the first material and the ultrasonic signal reflected at the boundary to the second material, so that the time of impingement of the reflected signal is clearly determined for the determination of propagation time.

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: An improved system for accurately determining the travel path of a host vehicle and the azimuth angle of a target vehicle through an automatic calibration that detects and compensates for FLS mis-alignment and curve sensor drift. Selected FLS tracking data (range and azimuth angle) are transformed to cartesian coordinates and characterized by a second order curve fitting technique to determine both FLS misalignment and curve sensor bias. Successively determined FLS misalignment and curve sensor bias values are averaged and used to correct subsequently supplied azimuth angle and curve sensor data, thereby compensating an underlying control for both sensor misalignment and curve sensor bias.

Abstract: A system is presented for enhancing sonar signals wherein Doppler echoes eived in the time domain from a sonar system are processed by digitizing, shifting to baseband, Fourier transforming to the frequency domain, applying a frequency stretching algorithm designed to expand low Doppler signals, retransforming the signal back to the time domain, reshifting from baseband to original center frequency, converting to analog and outputting the resultant enhanced Doppler time domain signals to either earphones of a sonar operator for audio monitoring or for further processing for visual display.

Abstract: A sonar depth sounder device and method for processing echo signals, reflected from objects within a body of water, utilizes a processor, a memory, a display, and a keypad connected to the processor. The receiver receives sonar signals indicative of ambient noise in an underwater environment. The processor receives an electrical signal representative of the ambient noise, and calculates a detection threshold. The detection threshold is calculated by multiplying a scaling factor times the variance of the signal indicative of the ambient noise, and adding that product to the mean of the signal indicative of the ambient noise in the underwater environment. A transmitter then excites a transducer which emits sonar pulses into a body of water, and a receiver receives reflected sonar echo signals. When the intensity of the reflected sonar echo signals is less than the detection threshold, the reflected echo signals are eliminated from processing.

Abstract: This disclosure relates to a system for automatically measuring and compensating for any angle of misalignment of a forward-looking sensor of a vehicle. The sensor provides data representing the azimuth angle and the range of a target such as another vehicle. For each angle and range reading of the sensor, the location point of the target is estimated; after a series of such readings, the trajectory line of the target is estimated. The angle of misalignment is estimated from the angle between the trajectory line and the path of travel of the host vehicle. In subsequent readings of the sensor, the estimated angle of misalignment is subtracted from the measured azimuth angle to produce an accurate azimuth angle of the target. The accurate azimuth angle is provided for use by another unit such as a collision warning system and/or an intelligent cruise control.

Abstract: A vibrating probe for detecting a threshold level within a vessel of fluent material, particularly a liquid, includes: an ultrasonic acoustic transducer assembly comprising a transducer element having a natural resonant frequency, and loading elements effective to shift that frequency to an effective resonant frequency of the assembly, the assembly being supported within the vessel and including a coupling member to couple the transducer acoustically to liquid reaching the threshold level, a transmitter generating pulses applied to the transducer element for repeatedly exciting the transducer element to cause the transducer assembly to resonate at its effective resonant frequency, a circuit for measuring the effective resonant frequency of the transducer over a ringdown period following cessation of each pulse, and a circuit for comparing the effective resonant frequency measured during the ringdown period following each pulse with a predetermined threshold level.

Abstract: An ultrasonic rangefinder capable of effectively removing high-level, directly transmitted wave components. The rangefinder can be used even at low temperatures. The rangefinder comprises an input signal-processing circuit, an output signal-processing circuit, and a gain control circuit inserted between the input and output signal-processing circuits. The output signal-processing circuit includes a reception amplification circuit and a detection circuit, the reception amplification circuit having an amplifier. The gain control circuit lowers the gain of the reception amplification circuit to raise the undetected and detected input voltage levels applied to the detection circuit. The gain control circuit comprises three control devices. The first control device is driven into conduction when its input pulse signal varies from a low level to a high level.

Abstract: A distance measuring apparatus includes a wave transmitting device for emitting a transmission wave. A wave receiving device is operative for receiving a reflection wave, which results from reflection of the transmission wave by a reflection object, as a reception wave. A time difference measuring device is operative for measuring a time difference between a moment at which the wave transmitting device emits the transmission wave and a moment at which the wave receiving device receives the reception wave. A distance calculating device is operative for calculating a distance to the reflection object on the basis of the time difference calculated by the time difference measuring device.

Abstract: One or more high-frequency ultrasonic transducers are used to measure the liquid level of tanks containing any type of fluid, but fuel in particular. The invention relates specifically to tanks that are subject to movement and vibration which generally makes the use of ultrasonic echoes unreliable for obtaining accurate level measurements. A special algorithm is used to obtain the temporal center of the distribution of echo arrival times over a preset time interval. From this temporal center of an echo distribution, the liquid level is readily obtained through the acoustic velocity, time and distance relationship. An annular piezoelectric plate, independently driven at low ultrasonic frequencies (kHz range), mounted on the tank bottom surrounds the high frequency ultrasonic transducer.