A method of operating electro-acoustical transducers such as PMUTs involves applying to the transducer an excitation signal over an excitation interval, acquiring at the transducer a ring-down signal indicative of the ring-down behavior of the transducer after the end of the excitation interval, and calculating, as a function of said ring-down signal, a resonance frequency of the electro-acoustical transducer. A bias voltage of the electro-acoustical transducer can be controlled as a function of the resonance frequency. An acoustical signal received can be transduced into an electrical reception signal and a damping parameter of the electro-acoustical transducer can be calculated as a function of the ring-down signal so that a cross-correlation reference signal can be synthesized as a function of the resonance frequency and the damping ratio of the electro-acoustical transducer. Such a cross-correlation reference signal can be used for cross-correlation with the electrical reception signal to improve the reception quality.

A method for acquiring the surrounding environment of a motor vehicle. The motor vehicle has at least one ultrasound sensor. The ultrasound sensor includes an ultrasound transducer for sending, the ultrasound sensor receiving acoustic environmental signals, in particular audible environmental signals, in that the ultrasound sensor is controlled in its evaluation in such a way that sound waves having frequencies below a resonant frequency of the ultrasound transducer, in particular audible sound waves, of an environmental signal are acquired and evaluated. Environmental signals are understood as acoustic signals that are not produced by the ultrasound transducer itself, but rather by an external sound source that in particular differs from the motor vehicle. This can be for example the siren of a rescue vehicle or emergency vehicle, or the horn of some other motor vehicle.

In a sonar system using a large array multielement sonar detector to detect reflected signals sent out by a sonar ping generator, the sent out sonar ping generator sends out varying frequency sonar signals during each ping, where the frequency is neither monotonically increasing or monotonically decreasing.

A device and method for reducing noise of an external measurement sensor of mobility, including a storage unit that stores measurement values of an external measurement sensor of mobility including an ultrasonic sensor measuring distance values between the mobility and an object outside the mobility; and an operation unit that generates a plurality of functions capable of being derived from the measurement values stored in the storage unit, derives a final function having the most measurement values within a first range, among the plurality of functions, derives an estimated value that is an expected value of the measurement value through the final function, and selects a candidate final value that is the closest to the estimated value within a second range, among actual measurement values at a time point corresponding to the estimated value, as a final value.

Techniques for calibrating presence-detection devices to account for various factors that can affect the presence-detection devices' ability to detect movement. Presence-detection devices may detect movement of a person in an environment by emitting ultrasonic signals into the environment, and characterizing the change in the frequency, or the Doppler shift, of the reflections of the ultrasonic signals off the person caused by the movement of the person. However, factors such as environmental acoustic conditions, noise sources, etc., may affect the ability of the presence-detection devices to detect movement. To calibrate for these factors, the presence-detection devices may use a loudspeaker to emit an ultrasonic sweep signal that spans different frequencies in an ultrasonic frequency range. The presence-detection devices may generate audio data using a microphone that represents the ultrasonic sweep signal, and analyze that audio data to determine an optimal frequency range and/or transmission power for subsequent ultrasonic signal transmissions.

A processing system for processing signals from a plurality of transducers of an ultrasonic sensor in order to determine characteristic information relating to an object detected by the ultrasonic sensor is provided. The system comprises a coupling device for transforming the signals received from the transducers into pulses, and a pulse processing unit for determining the characteristic information based on the pulses delivered by the coupling device. The coupling device comprises: a thresholding unit for applying, for each signal received from a transducer, thresholding to a signal derived from the signal received from the transducer and extracting directional information contained in the phase of the derived signal; a transformation unit for transforming the derived signal into pulses containing the phase of the signal, using the information extracted by the thresholding unit.

Disclose are various approaches for optimizing operation of an autonomous wireless mobile asset monitoring system. The approaches involve detecting the presence of cargo in a mobile asset. First, if energy conservation is a requirement of the system, each zone of the mobile asset is scanned until cargo is detected in one of the zones. Then, the results of the scan are transmitted to backend infrastructure. Alternatively, if energy conservation is not a requirement of the system, every zone of the mobile asset is scanned and the results of the scan are transmitted to backend infrastructure.

The present invention relates to a method for computational noise compensation for an ultrasonic sensor system (1) that is mounted in a concealed manner, in particular for a vehicle with a wall material (2), including the following steps: detecting reference surroundings information (100) comprising noise signal information (3) relating to a wall material (2) and/or airborne sound signal information (4), using an ultrasonic sensor (5) of the ultrasonic sensor system (1); storing the reference surroundings information (200); detecting real-time surroundings information (300) comprising noise signal information (3) relating to the wall material (2) and/or airborne sound signal information (4), using the ultrasonic sensor (5); and forming a difference signal between the pieces of surroundings information (400) of reference surroundings information and real-time surroundings information, using a computational unit (6).

The present invention also relates to a system for computational ultrasound compensation having means for performing the steps of the method. The present invention further relates to a vehicle having the system for computational ultrasound compensation. The present invention furthermore relates to a computer program, to a data carrier signal, and to a computer-readable medium.

A method for detecting a moving object in a scene includes providing sampled ultrasonic echo signals from the scene; determining echo envelopes of the sampled ultrasonic echo signals; determining differentials of successive echo envelopes for providing echo envelope differentials; determining the absolute values of the echo envelope differentials; and conducting a classification based on the determined absolute values of the echo envelope differentials for determining a relative movement of the moving object.

One embodiment provides a method comprising acquiring, via one or more microphones of a device in a spatial area, a signal representing at least one echo of an ultrasound emitted via one or more loudspeakers of the device. The method further comprises applying digital signal processing to the signal to determine a signal-to-noise ratio (SNR) of the signal, and estimating one or more properties of a moving reflector in the spatial area based on the SNR of the signal.