Abstract: A distance measuring device includes a transmitter for transmitting an acoustic signal at a distant object, an acoustic signal receiver for receiving a reflected acoustic signal reflected from the distant object, a temperature sensor detecting air temperature, a humidity sensor detecting air humidity, an amplifier amplifying the reflected acoustic signal, a comparator coupled to the amplifier comparing the amplified reflected acoustic signal with a reference and generating a comparator output when the level of the amplified reflected acoustic signal exceeds the reference, a gain controller increasing the gain from transmitting an acoustic signal until the comparator output is generated, a threshold generator providing the reference to the comparator and decreasing the reference at an exponential rate from transmitting the acoustic signal until the comparator output is generated, and a controller determining use of only the air temperature, velocity of the acoustic signal, and distance traveled from transmitti

Abstract: A proximity detector for use in a mobile telephone having at least a microphone and a loudspeaker operatively connected to a signal processor is presented. The proximity detector includes data processing and control modules having a module for controlling the signal processor for activating the loudspeaker to reproduce an acoustic control signal. A correlator correlates a control signal received directly by the microphone and a control signal being reflected from a user of the telephone and then received by the microphone to determine the distance between the telephone and the user. A signal level controller controls the signal processor to vary the signal level of an audible signal reproduced by the loudspeaker depending on the determined distance between the telephone and the user.

Abstract: System for evaluating the traffic environment of a motor vehicle and for influencing the speed of the motor vehicle in its own traffic lane, comprising an electronic control unit, which is connected to a signal transmitter that produces a signal characteristic of the desired speed of the motor vehicle, a signal transmitter that produces a signal characteristic of the yaw of the motor vehicle about its vertical axis, a signal transmitter that produces a signal, which is characteristic of the articles situated, in the direction of travel of the motor vehicle, in front of the motor vehicle in terms of their spacing and orientation relative to the motor vehicle and which is the speed relative to the speed of the system motor vehicle and/or the spacing relative to the system motor vehicle and/or the angular offset or the cross track distance relative to the vehicle longitudinal axis of the system motor vehicle, and a signal transmitter that produces a signal characteristic of the speed of at least one wheel of the

Abstract: Engaging portions of an ultrasonic sensor apparatus are engaged with engaging portions of a holding member at a first angular position of the ultrasonic sensor apparatus when the ultrasonic sensor apparatus is axially installed to the holding member, which is in turn installed to a bumper. At the time of uninstalling the sensor apparatus from the holding member, one of the engaging portions is radially outwardly disengaged from a corresponding one of the engaging portions of the holding member, and then the sensor apparatus is rotated to a second angular position to release engagement between the rest of the engaging portions of the sensor apparatus and the rest of the engaging portions of the holding member. Thereafter, the sensor apparatus is axially pulled away from the holding member to uninstall the sensor apparatus from the holding member.

Abstract: A system and method of performing sonar range estimations in a noisy sonar environment. The system includes a sensor, a transmitter, a receiver, a plurality of band-pass filters, a cross correlator, and a data analyzer. The transmitter transmits a pulse through a transmission medium. The pulse travels through the transmission medium until it strikes an object, which returns an echo to the sensor. The sensor provides the echo to the receiver, which provides an indication of the echo to the band-pass filters. The respective band-pass filters provide filtered versions of the echo and pulse to the cross correlator, which performs multiple cross correlation operations on the filtered echo and pulse. The cross correlator provides output data to the data analyzer, which uses the data to estimate the SNR in the environment and to determine a pulse center frequency corresponding to the estimated SNR.

Abstract: An obstacle detecting apparatus includes an image input unit for receiving images inputted respectively from a plurality of image pick-up devices and accumulating the input images, a feature calculating unit for calculating predetermined, specific feature quantities in the respective accumulated images, a feature comparing unit for comparing the feature quantities, and a result judging unit for judging the presence or absence of an obstacle on the basis of the comparison result. The obstacle detecting apparatus can thus detect an obstacle present on the road by distinguishing the obstacle from a mere object causing no obstruction to driving of the vehicle.

Abstract: A method and apparatus for use with a non-frangible object detection mechanism on an agricultural harvester, the detection mechanism including a sensing surface and a sensor for sensing force applied to the sensing surface that is associated with a foreign object adjacent the sensing surface, the harvester including a transport surface along which harvested materials are transported toward the sensing surface, the apparatus including at least first and second ramp members positioned between the transport surface and the sensing surface, the ramp members separated by a gap, each ramp member including a front ramp surface that extends between a front ramp end adjacent the transport surface and a ramp member apex, the ramp member apexes positioned at a location higher than the sensing surface and proximate the sensing surface, wherein, as harvested material and non-frangible objects are conveyed along the transport surface and toward the sensing surface, at least a portion of the harvested material passes betwee

Abstract: An apparatus for estimating direction of arrival of signal is provided that has excellent performance in terms of angular resolution and the number of signals that can be identified. In an array sensor comprising a plurality of sensor elements, the two outermost sensor elements are alternately selected by a switch for use as a transmitting sensor, and the other sensor elements are selected in time division fashion as receiving sensors. With this arrangement, the effective aperture is increased to about twice the physical aperture, to improve angular resolution in a direction-of-arrival estimator.

Abstract: A target tracking arrangement predicts the state of a target. The predictor may be a Kalman filter. In the presence of a target which is maneuvering, the prediction may be in error. A maneuver detector is coupled to receive residuals representing the difference between the predictions and the target state. The maneuver detector is matched to the predictor or Kalman filter to thereby tend to reduce the undesirable effects of system noise. The matching may be of the frequency response.

Abstract: Arrangement with an acoustic array with a sound velocity meter, suitable to be arranged under water. The acoustic array is able to receive acoustic signals from an underwater device and to provide acoustic array output data to a processing arrangement such that the processing arrangement can perform in real-time, a calculation of a position of the underwater device relative to the acoustic array based on the acoustic array output data. The sound velocity meter is able to measure velocity of sound in fluid layers just below a vessel floating on the water and to provide sound velocity meter output data to the processing arrangement such that the processing arrangement can correct the calculation of the position of the underwater device based on the sound velocity meter output data in real-time.

Abstract: The apparatus includes transmitter-receiver units (10, 20) for emitting acoustic signals in the form of beams (F1, F2) directed rearwardly of the stern and for receiving acoustic signals reflected by the fixed structure (B, C). The number of transmitter-receivers and the beam angles of the respective beams are determined so as to include substantially the entire area behind the stern in their field of view. Each transmitter-receiver includes a transducer for converting input electrical signals into output acoustic signals and for converting reflected acoustic signals into output electrical signals which are supplied to an electronic processor unit. On the basis of electrical input and output signals, the processor unit determines the instantaneous distance between the vessel and the fixed structure. A visual and/or acoustic signalling device is connected to the processor unit for emitting a visual and/or acoustic signal in real time indicating the instantaneous distance determined.

Abstract: The selection of multiple, suitably designed, demodulation reference signals can enable the measurement of a vehicle's speed using continuously transmitted frequency modulated (CTFM) signals. The unique solution of vehicle speed can be used to resolve the range Doppler ambiguity found in conventional CTFM sonar and radar systems. This can enable continuous range and speed estimates of high-speed vehicles with an attendant reduction in transmit power relative to pulse-echo systems with similar measures of performance due to the 100% duty cycle.

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: A system and method for preemptively sensing an object in the potential drive path of an automotive vehicle and selectively operating both a collision countermeasure system and a parking assistance system aboard the automotive vehicle are disclosed herein. The system includes a radar sensor, ultrasonic sensors, and a data processing system mounted aboard the automotive vehicle. The data processing system is electrically connected to the radar sensor, the ultrasonic sensors, the collision countermeasure system, and the parking assistance system. The sensors are operable to cooperatively sense the position of the object in the potential drive path of the automotive vehicle and accordingly transmit sensor data to the data processing system. The data processing system is operable to receive the sensor data, selectively process the sensor data, and accordingly transmit operating instructions to the collision countermeasure system and the parking assistance system so as to selectively operate both systems.

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: An echo-signal monitoring device having a plurality of transceiver units for transmitting signals and receiving the echoes reflected by an external object and an analyzer unit for estimating the distance from the monitoring device to the external object on the basis of the received echoes is characterized in that the device has an operating mode for calculating the relative position of the transceiver units from one another on the basis of the reflected echoes.

Abstract: A sonar system includes a forward looking array which is embedded in a cavitator for generating a gaseous cavity which minimizes hydrodynamic noise resulting from turbulent pressure fluctuations. A marine vessel incorporating the sonar system includes a hull, a hydrofoil suspended beneath the hull by a strut, and a cavitator for generating a laminar flow over the hydrofoil and for creating a cavity for eliminating turbulent flow contact. The cavitator is located at a leading edge area of the hydrofoil. The sonar array is embedded into the cavitator.

Abstract: The present invention discloses a universal replaceable back radar, wherein a head sleeve and a vehicle-reversing module thereof are separately designed and coated, an ultrasonic head is coupled to the connecting block of the vehicle-reversing module, an angle-adjust pad is also clamped to the connecting block of the vehicle-reversing module, and a big and a small hook platelets each with different heights are separately installed at both sides of one face of the angle-adjust pad and press against the internal face of a downward-tilt or an upward-tilt bumper. The universal replaceable back radar of the present invention can simplify the assemblage thereof and save the coating step thereof and its man-hour.

Abstract: A code applying device is provided which can efficiently manufacture an information recording paper roll having a code relating to the information recording paper. The code applying device includes a tubular body holding section which holds a tubular body and can rotate around an axis; a code forming section forming a code, which expresses specific information, on an end surface of the tubular body held by the tubular body holding section; and a control section rotating the tubular holding section which is holding the tubular body, and applying the code to the end surface of the tubular body along a peripheral direction.

Abstract: This invention exploits the synchronization properties of coupled, nonlinear oscillators arrays to perform power combining, beam steering, and beam shaping. This architecture utilizes interactions between nonlinear active elements to generate beam patterns. A nonlinear array integrates the signal processing concurrently with the transduction of the signal. This architecture differs fundamentally from passive transducer arrays in three ways: 1) the unit cells are nonlinear, 2) the array purposely couples the unit cells together, and 3) the signal processing (beam steering and shaping) is done via dynamic interactions between unit cells. The architecture extends to both 1- and 2-dimensional arrays.

Abstract: The invention is a digital sounder module and its method for detection. The digital sounder module includes a sonar carrier wave producing means, a band-pass filter, a pre-amplifier for providing a high sensitivity and extending a wide dynamic range, and an analog-to-digital converter for providing a digital implementation of a superheterodyne detector and producing an intermediate frequency. The digital sounder module also includes a programmable logic device for controlling a gain of the pre-amplifier and for digitally filtering the intermediate frequency and a microprocessor. The method implemented by the controlled per-amplifier gain processes the return echo signal by controlled ramp up of the gain over time to compensate for the change in signal strength in proportion to the length of the return path.

Abstract: A sonar system and method of use capable of discriminating a direct acoustic signal present at 60 dB or more above the acoustic echo signal.

Abstract: An altitude measuring system and method for aircraft is provided. The altitude measuring system includes altitude sensors for providing data to an altitude processing unit. The altitude processing unit spatially averages each output to determine a mean altitude. Pitch and roll are accounted for by correction. A method of determining aircraft altitude from a plurality of altitude sensors includes receiving altitude sensor data from each sensor and spatially averaging the altitude sensor outputs to determine aircraft altitude. A method of estimating the maximum height of an ocean surface includes receiving a plurality of altitude sensor data and determining a mathematical description of the ocean surface from the sensor data. The maximum probable wave height of the ocean surface is estimated from the mathematical description. From the maximum wave height, a cruise altitude may be determined.

Abstract: An arrangement for fill level measurement is provided, with which accurate fill level measurement on a continuing basis is possible, including a container (3) containing a fill substance (1) whose fill level is to be measured, a fill level measuring device (5) arranged at the container (3) and operating according to the travel time principle, an apparatus (11, 13) for registering a filling and/or emptying of the container (3), an auxiliary unit (19), which by means of the filling and/or emptying registered by the apparatus (11, 13), determines an instantaneous change in fill level (VL) or an instantaneous change in material flow rate, and makes such available to the fill level measuring device (5) for determining the fill level (L) to be measured.

Abstract: An airborne sonar collision avoidance system is disclosed. The system compensates for changes in temperature in real time to provide more accurate sonar detection. In addition, the sensors are arranged in a communications network that allows for the sensors to be programmed at run time, thus providing the ability to relocate the sensors without having to pre-program the sensors before the sensors are installed onto a different location.

Abstract: Method and apparatus for application of echolocation to robot guidance and assisting the blind. The method is based on the echolocation of bats. It combines a source of pulsed ultrasound (100) with a recently-developed acoustic vector probe (AVP) (200) into an echolocation instrument (1000), together with a data-acquisition system (300), a digital signal processor (400) and an output device (500). The source emits pulses of ultrasound of about 35 kHz over a beam angle of approximately 100 degrees and the AVP detects backscattered pulses from a discrete distribution of acoustic highlights on surrounding objects. The ultrasonic sound pressures of the backscattered pulses are heterodyned down to lower frequencies so that the signal processor can make an accurate determination of the sound-intensity vector for each pulse.

Abstract: A method for processing echoes in a time-of-flight ranging system or level measurement system. The method comprises a recursive descent parser which is applied to an echo profile to process and identify potential echoes. In another aspect, the method provides for processing the ring down portion of the echo profile.

Abstract: A sensor system for determining distances is provided. A predefining unit controls an amplifier unit and/or a sensor unit as a function of selectable predefined values for a detection cycle. Contrary to known sensor systems, different detection cycles are implementable in a simple manner using this procedure.

Abstract: A device for detecting objects, especially used as a parking assistance device in a motor vehicle, includes a plurality of distance sensors, at least one microcontroller configured to control the distance sensors and an output unit. The distance sensors emit a signal in accordance with an identifier that is modified over time by the microcontroller.

Abstract: A portable ultrasound height measuring apparatus, which comprises a display module and a measuring module. Wherein the display module comprises a LCD, a speaker, a transparent plank and a skidproof pad. The measuring module comprises an ultrasound emitter, an ultrasound receiver, a start button, a set fingerboard, and under the set fingerboard a microprocessor. The apparatus measures height of measured person by emitting an ultrasound signal from the emitter and receiving a reflecting signal by the receiver, then displays value on the LCD. The display module and measuring module are jointly connected together to make the display module able to rotate, open, and close in a set range of angle relative to the measuring module.

Abstract: An ultrasonic sensor includes a piezoelectric vibrator, a reverberation measuring device and a compensating device. The piezoelectric vibrator vibrates to transmit an ultrasonic wave, receives a reflected wave of the transmitted ultrasonic wave and produces an output signal corresponding to vibration of the piezoelectric vibrator. The reverberation measuring device measures a reverberation period of the piezoelectric vibrator from the output signal. The compensating device compensates for an operation characteristic of the piezoelectric vibrator in accordance with the measured reverberation period. Thus, the ultrasonic sensor can decrease a reverberation period, which may cause reduction in detection accuracy and impossibility of detection of an obstacle at a short distance.

Abstract: An acoustic-propagation-time measuring apparatus includes an acoustic transmitting and receiving section having an acoustic element capable of transmitting and receiving acoustic waves, an A/D converter which converts an echo signal reflected from a target object to be measured into a digital signal, an inverse-analysis section that converts the digital echo signal into an impulse signal through inverse analysis where the digital echo signal is multiplied by an inverse matrix, a calculating section that measures an acoustic propagation time and a time difference based on the digital echo signal converted to the impulse signal, and a display section which displays the acoustic propagation time and time difference calculated by the calculating section.

Abstract: A system and method are presented for determining the detection and location of persons and objects using ultrasonic acoustic sensors. The system allows detection of stationary and moving persons and other objects, through atmospheric conditions, to a distance of at least 300 feet. The invention further provides for enhanced signal processing through the use of arrays of transmitters and receivers, where one or more transmitter arrays may be oriented substantially perpendicularly to one or more receiver arrays, allowing high directionality and good rejection of reverberations, background noise, clutter and objects not of interest.

Abstract: The present invention provides for a system and method for measuring the height of a guest at a theme park, including employing an ultrasonic emitter and sensor to determine height. The park may have a plurality of different predetermined minimum height ranges or categories for certain rides and attractions, which must be met by a guest before the guest is allowed to participate. The results of the height measurement are provided on indicia and given to the guest to use at rides throughout the park. The device may be a wristband affixed to the guest, and displaying a color or symbol based on the height of the guest. The guest would be allowed to participate in an attraction provided the color code matches the minimum requirements of the attraction. This present invention may eliminate the need to check the height of the guest at each ride.

Abstract: An improved fish finding device and method for detecting and distinguishing marine life from a sonar reflected marker that generates artificial echoes comprises steps of 1. transmitting of sonar waves 2. receiving of sonar echoes 3. distinguishing the sonar echoes reflected from a sonar reflected marker from the marine life by the difference of frequency, intensity, waveform and duration of the echoes and converting echoes into signal using a microprocessor and 4. displaying the echoes signal of the sonar reflected marker as an icon different from that of the marine life. The relative distance of the sonar reflected marker and the marine life could also be calculated by a microprocessor. A fish nearby alarm sounds when fish swims within a preset value of distance. The improved fish finding device and the fish finding method guide the user to adjust accurately the bait next to fish.

Abstract: A sound collecting device is provided which is designed to minimize adverse effects on an output caused by exposure of an electroacoustic transducer to the air. The device includes an electroacoustic transducer and a vibrating circuit. The transducer is exposed to the air and responsive to input of a sound wave to produce a corresponding acoustic signal. The vibrating circuit vibrates the transducer to shake foreign substances such as dust or drops of water from the transducer. In a modified form, an electromagnetic sensor is provided which measures an electromagnetic noise transmitted to the transducer and which removes the electromagnetic noise from an output of the transducer to produce a noiseless acoustic signal.

Abstract: The invention is a digital sounder module and its method for detection. The digital sounder module includes a sonar carrier wave producing means, a band-pass filter, a pre-amplifier for providing a high sensitivity and extending a wide dynamic range, and an analog-to-digital converter for providing a digital implementation of a superheterodyne detector and producing an intermediate frequency. The digital sounder module also includes a programmable logic device for controlling a gain of the pre-amplifier and for digitally filtering the intermediate frequency and a microprocessor. The method implemented by the controlled per-amplifier gain processes the return echo signal by controlled ramp up of the gain over time to compensate for the change in signal strength in proportion to the length of the return path.

Abstract: A device for detecting parking spaces for vehicles includes a distance-measuring beam-type sensor system disposed on a road vehicle, and a signal processing system. The distance-measuring beam-type sensor system directs a measuring beam into an area in front of the vehicle so as to detect free areas in the traffic space that are potential parking spaces. The signal processing unit examines, upon a detecting of a free area, the dimensions of the free area and the suitability of the free area for parking.

Abstract: A current loop control circuit for a process variable transmitter coupled to a receiver at a remote location through a two-conductor current loop. The current loop control circuit efficiently utilizes the current in the loop to produce an optimal voltage and current for the operation of the process variable measurement transmitter.

Abstract: A measuring apparatus includes a housing with a retractable tape, a waveform range finder, and a laser pointer disposed within the housing. The retractable tape includes indicia corresponding to a distance. A save button is further disposed on the housing, wherein upon the depression of the save button, the distance measured by waveform range finder is saved to a memory. A display on the housing indicates the dimension measured by the waveform range finder.

Abstract: A proximity detector for use in a mobile telephone having at least a microphone and a loudspeaker operatively connected to a signal processor is presented. The proximity detector includes data processing and control modules having a module for controlling the signal processor for activating the loudspeaker to reproduce an acoustic control signal. A correlator correlates a control signal received directly by the microphone and a control signal being reflected from a user of the telephone and then received by the microphone to determine the distance between the telephone and the user. A signal level controller controls the signal processor to vary the signal level of an audible signal reproduced by the loudspeaker proportionally to the determined distance between the telephone and the user.

Abstract: The invention relates to a device for distance measurement, comprising a housing (24) which is provided with an integrated emitting unit (32) for a measuring signal (34, 36) and a receiving unit (38) for the measuring signal (34, 36) returned from a target object (16), and an evaluation unit (46) for determining the distance (d) between at least one reference point (14) of the housing (24) and the target object (16, 18), a display device (50) which reproduces said distance (d), and at least one receiving element (28) which is connected to the housing (24) and receives a holding element (12, 13) of the device. According to the invention, means (66, 84, 86) are provided in or on the housing (24) of the device (10) for detecting an inserted holding element (12, 13) for the housing (24). Said means automatically transmit the reference point (14) of the distance measurement to the evaluation unit (46), said reference point being used for a measurement with the aid of said holding element (12, 13).

Abstract: A method of operating a pulse echo ranging system comprising a transducer assembly for providing transmission and reception of high frequency energy pulses at substantially different plural frequencies. The method uses signals received by the transducer assembly to generate an echo profile for signals received at at least a first of the frequencies to enhance the recovery of data beyond that obtained from the first signal alone.

Abstract: A position locating device for identifying the distance and direction from a first object located with a user to a second object. The first object transmits a signal to the second object. The second object returns a signal to the first object. Microphones are arranged around the first object such that the time at which a microphone receives the returned signal is related to the direction of the second object relative to the first object. A receiver located at the first object decodes and analyzes the signal and its intensity to determine the distance of the second object.

Abstract: A case of tilt angle measuring apparatus is composed of a case body for housing ultrasonic sensors and a cover for covering a top of the case body, and the case body includes a bottom plate having windows for exposing the ultrasonic wave transmitting/receiving faces of the ultrasonic sensors, a side plate extending upward from the peripheral edge of the bottom plate and abutting against the bottom surface of the cover, and horn parts extending downward from the bottom plate so as to surrounding the windows.

Abstract: A pulse offset calibration method for a pulse-echo level measurement system. The pulse-echo level measurement system includes a transducer for transmitting calibration acoustic pulses and receiving echo pulses. A receiver converts the echo pulses into corresponding pulse profile signals having a leading edge. A static delay interval is defined on the leading edge corresponding to the time interval between the reception of the echo pulse and the response by the receiver. A dynamic delay interval is defined on the leading edge corresponding to the time response characteristics of the transducer and the receiver. The static delay interval and the dynamic delay interval are summed to determine the offset time interval for the echo pulse. The offset time interval is subtracted from the measurements to provide the true duration for the time of flight.

Abstract: A back-up detecting device with a distance reset capability has a controller with an intensity analysis program and a distance reset function. When an ultrasonic transceiver is installed underneath a vehicle chassis forward of the rear end, a distance correction called a distance pad is measured, calculated and stored in memory by the distance reset function. The distance pad is the distance between the ultrasonic detector and the rear end of the vehicle. When the distance reset capability is used to determine a distance pad for each ultrasonic transceiver, the back-up detecting device presents accurate distances to objects without regard to the structure of the vehicle body without having to alter system hardware or software. Thus the back-up detecting device is suitable for large vehicles of varied shapes and sizes.

Abstract: Method and apparatus for acoustic detection, location and identification of a buried object using a source emitting bursts of sound that penetrate the ground and return echoes from the object to an array of acoustic vector probes (200) located above the ground. Echoes recorded at the probes in the array, are converted to digital form and fed into a digital signal processor (400) which computes the sound-intensity vector at each probe. Results are displayed on a computer screen or other device (500) permitting an operator to interact with and control the apparatus. The processor controls gating of the bursts of pulsed sound and the duration of the reception of echoes by the array. Additional related features and methods are disclosed.

Abstract: An airborne sonar collision avoidance system is disclosed. The system compensates for changes in temperature in real time to provide more accurate sonar detection. In addition, the sensors are arranged in a communications network that allows for the sensors to be programmed at run time, thus providing the ability to relocate the sensors without having to pre-program the sensors before the sensors are installed onto a different location.

Abstract: A method and system for echo processing a receive signal using autocorrelation. A receive signal is sampled, digitized and high-pass filtered. A correlation signal is created by adding the filtered signal to a copy of the filtered signal shifted by a time unit. A set of correlation signals is created by repeating the process for a range of time units corresponding to a set of sequential sample points. Each correlation signal has a correlation indicator evidencing the strength of the correlation. The correlation signal having the highest correlation strength is identified, and the time shift used to create it is identified as the time of flight of the echo pulse. The echo distance is then calculated based upon the time of flight and the speed of propagation of the echo in the environment. The correlation indicator may the maximum peak value of the correlation signal.