An external calibrating device (10) for a measurement device, which may be an acoustic camera. The calibrating device (10) includes a sound source (11) and a light source (12), which are preferably pointed to the same direction. This direction can be a horizontal direction, where the sources (11, 12) locate on the same vertical side surface of the calibrating device (10). An IR LED can be used as the light source (12). The measurement device may instruct a user how to place and align the measurement device during the calibration process. Guidance is given by instructions, volume range information, and focusing lines on the screen. When the instructions are fulfilled, the user may acknowledge the finished calibration process.

A hydrophone used for measuring acoustic energy from a high frequency ultrasound transducer, or a method of manufacturing the membrane hydrophone. The membrane assembly is supported by the frame and comprises a piezoelectric. The hydrophone also includes an electrode pattern formed within the piezoelectric to define an active area. In addition, the hydrophone includes a built in-situ coaxial layer connected to the active area.

A method for contact detection for an ultrasonic sensor system installed in a concealed or unconcealed manner is disclosed. The method involves detecting reference surroundings information, comprising a time profile of a signal with: noise signal information relating to a wall material and/or airborne sound signal information, using an ultrasonic sensor of the ultrasonic sensor system; storing the reference surroundings information; detecting real-time surroundings information, comprising a time profile of a signal with: noise signal information relating to the wall material and/or airborne sound signal information and/or object sound signal information relating to an object in contact with the wall material, using the ultrasonic sensor; and forming a difference signal between the surroundings information of reference surroundings information and real-time surroundings information, using a computational unit. The difference signal can be interpreted in a further step.

A method for contact detection for an ultrasonic sensor system installed in a concealed or unconcealed manner is disclosed. The method involves detecting reference surroundings information, comprising a time profile of a signal with: noise signal information relating to a wall material and/or airborne sound signal information, using an ultrasonic sensor of the ultrasonic sensor system; storing the reference surroundings information; detecting real-time surroundings information, comprising a time profile of a signal with: noise signal information relating to the wall material and/or airborne sound signal information and/or object sound signal information relating to an object in contact with the wall material, using the ultrasonic sensor; and forming a difference signal between the surroundings information of reference surroundings information and real-time surroundings information, using a computational unit. The difference signal can be interpreted in a further step.

In some embodiments, a method, apparatus and computer program for reducing noise from an audio signal captured by a drone (e.g., canceling the noise signature of a drone from the audio signal) using a model of noise emitted by the drone's propulsion system set, where the propulsion system set includes one or more propulsion systems, each of the propulsion systems including an electric motor, and wherein the noise reduction is performed in response to voltage data indicative of instantaneous voltage supplied to each electric motor of the propulsion system set. In some other embodiments, a method, apparatus and computer program for generating a noise model by determining the noise signature of at least one drone based upon a database of noise signals corresponding to at least one propulsion system and canceling the noise signature of the drone in an audio signal based upon the noise model.

An object of the invention is to provide an ultrasonic probe, an ultrasonic diagnostic device, and a manufacturing method of the ultrasonic probe, which are capable of reducing a product defect rate. An ultrasonic probe according to one embodiment includes a plurality of channels. Each of the plurality of channels includes a vibrator that outputs an ultrasonic wave, and a transmission circuit unit that changes an output in response to an input transmission signal and causes the vibrator to output the ultrasonic wave by driving the vibrator with the output. Here, the transmission circuit unit includes a stop signal holding circuit that holds a stop signal when the stop signal is input in advance, and selects whether to change the output in response to the transmission signal based on whether the stop signal is held.

An electronic device includes a processor, and a memory containing instructions that, when executed by the processor, cause the electronic device to learn a sound emitted by a legacy device and to issue an output when the electronic device subsequently hears the sound. For example, the electronic device can receive a training input and extract a compact representation of a sound in the training input, which the device stores. The device can receive an audio signal corresponding to an observed acoustic scene and extract a representation of the observed acoustic scene from the audio signal. The electronic device can determine whether the sound is present in the observed acoustic scene at least in part from a comparison of the representation of the observed acoustic scene with the representation of the sound. The electronic device emits a selected output responsive to determining that the sound is present in the acoustic scene.

A time at which a failure of a noise level meter has occurred is accurately determined. The present invention relates to a noise measuring device including a noise level meter having a main microphone capable of measuring noise, and a sub microphone capable of measuring noise at the same time as the main microphone. The present invention also relates to a failure diagnosing system having the noise measuring device and a failure diagnosing device capable of diagnosing a failure of the main microphone. The present invention also relates to a failure diagnosing method for diagnosing a failure of the main microphone. In the failure diagnosing system and the method, the presence or absence of a failure of the main microphone in the noise level meter is diagnosed based on the comparison between main and sub noise data obtained by the main and sub microphones and respectively in each of a plurality of recording periods.

A method for controlling at least two mechanical oscillators, more particularly in a motor vehicle, where each oscillator oscillates at a frequency during operation and where the frequency can be controlled by the power applied to the oscillators, includes arranging a single sound transducer at a distance from the oscillators and capturing an electrical signal, where the electrical signal is subjected to a Fourier transform and thus a Fourier spectrum is determined. The frequency of each oscillator is determined from extreme values of the Fourier spectrum.

A method for controlling at least two mechanical oscillators, more particularly in a motor vehicle, where each oscillator oscillates at a frequency during operation and where the frequency can be controlled by the power applied to the oscillators, includes arranging a single sound transducer at a distance from the oscillators and capturing an electrical signal, where the electrical signal is subjected to a Fourier transform and thus a Fourier spectrum is determined. The frequency of each oscillator is determined from extreme values of the Fourier spectrum.