582 results about "Acoustic frequency" patented technology

A method is proposed for automatically adjusting the filter parameters—center frequency, quality and amplification or attenuation—of at least one digital equalizer which is a component of a reproduction device for audio signals in a vehicle passenger compartment. To that end, first of all, the acoustical frequency response of the passenger compartment is ascertained. The inadequacies in the acoustics of the passenger compartment in the form of local maxima and minima in the measured frequency response are then determined. On this basis, the filter parameters are adjusted automatically so that at least a portion of these inadequacies is compensated. A reproduction device for audio signals for implementing this method is also proposed.

Acoustic device including a member extending transversely of its thickness and capable of sustaining bending waves at least over an intendedly consequentially acoustically active area of the transverse extent of said member, the member having, by reason of orderly design methodology disclosed and claimed, a distribution of resonant modes of its natural bending wave vibration at least over said area that is dependent on values of particular parameters of said members, including geometrical configuration and directional bending stiffness(es), which values have been selected to predetermine said distribution of natural resonant modes being consonant with required achievable acoustic action of said member for operation of said device over a desired operative acoustic frequency range.

Method and system for automatically adjusting a hearing aid. The method includes measuring an acoustic reflectance associated with an ear canal as a function of an incident pressure and an acoustic frequency, processing information associated with the measured acoustic reflectance, determining a reflectance slope based on, at least, information associated with the measured acoustic reflectance, and adjusting, at least, one parameter associated with the hearing aid based on, at least, information associated with the reflectance slope. The reflectance slope is associated with a reflectance component varying with the incident pressure.

A retinal stimulation and prosthetic device is provided that includes at least one ultrasonic transducer having a focused ultrasonic signal, where the focused ultrasonic signal includes an acoustic frequency, a spot size, a temporal pattern, a pulse duration and a power capable of stimulating retinal neurons when the at least one ultrasonic transducer is disposed proximal to an eye.

A microwave cooking appliance includes an oven cavity, a magnetron and a load sensing system. The load sensing system is used to detects the presence of a load in the oven cavity by introducing a high frequency energy burst into the oven cavity, with the energy burst being reflected back. A controller, based on a time period between emitted and reflected signals, determines whether a load is present in the oven cavity. If no load is present, operation of the magnetron is terminated. Preferably, the high frequency energy burst is an ultrasonic acoustic frequency energy burst in a range between approximately 10 kHz and 100 kHz.

Various embodiments of the present invention provide for a photoacoustic imaging probe for use in a photoacoustic imaging system, whereby the probe is comprised of a cohesive composite, acoustic lens incorporating aspheric geometry and exhibiting low or practically no measurable dispersion of acoustic waves constructed of at least one material with a low acoustic impedance and attenuation and a relatively low acoustic velocity and at least one other material with a low acoustic impedance and attenuation and a relatively high acoustic velocity. The probe is housed in a conduit filled with a low acoustic velocity and low acoustic impedance fluid such as water or mineral oil. The lens may be designed as a telecentric lens, an acoustic zoom lens, a catadioptric lens, or a reflective lens. The lens focuses acoustic waves on an acoustic imager which detects the image. The acoustic imager may be designed as a 2 dimensional array of transducers. Research to date indicates that within the range of acoustic frequencies of interest, 1 MHz-50 MHz and preferable 2 MHz-10 MHz, there exists little velocity variation within the materials of interest, and the lens design approach may currently be considered to be essentially monochromatic. The acoustic waves can be generated when an emitting light source illuminates a test subject comprising materials that generate acoustic waves at differing intensities and / or frequencies when illuminated with light, for example tissue containing blood vessels, wherein the blood vessels excite and generate an acoustic pulse. The probe has an acoustic window made of a material with low acoustic impedance which allows the acoustic pulse to enter the probe without distortion and then may be reflected by a mirror onto the acoustic lens. The probe may include the emitting light source and an optical window to allow light emitting from said light source to illuminate the test subject.

An acoustic sensor and a method of fabricating an acoustic sensor are provided. The acoustic sensor includes at least one photonic crystal structure and an optical fiber having an end optically coupled to the at least one photonic crystal structure. The acoustic sensor further includes a structural portion mechanically coupled to the at least one photonic crystal structure and to the optical fiber. The at least one photonic crystal structure, the optical fiber, and the structural portion substantially bound a region having a volume such that a frequency response of the acoustic sensor is generally flat in a range of acoustic frequencies.

The specification and drawings present a new method, apparatus and software product for providing flexible audio communication solutions using ear-devices utilizing, e.g., electrode transducers with one or more sensors comprising a surface resonator cavity sensitive to a predetermined acoustic frequency range for using, for example, in headsets and hearing aids. The ear-device can be configured for inserting it into a human ear for a handsfree operation and the sensors can be configured to detect human tissue vibrations using the surface resonator cavity. The acoustic communication solutions with these ear-devices may include: providing two-way communications in normal conditions as well as in noisy conditions, providing protection of hearing, recording the true sound field bin-aurally, providing a playback capability, providing volume enhancement and equalization for persons with hearing defects, etc.

A dual-frequency coaxial earphone includes a frame, a shared yoke, a high frequency speaker part, and a low frequency speaker part. The high frequency speaker part and the low frequency speaker part are coaxially arranged at inside and outside of the shared yoke, and are coaxial with a central opening of the frame. Further, a permanent magnet of the higher frequency speaker part is contrary, in polarity, to an annular magnet of the low frequency speaker part. Therefore, acoustic frequency of the low frequency speaker part can be phase-countered by passing thereof through an acoustic annular recess, so that the acoustic frequency of the low frequency speaker part has the same phase as the acoustic frequency of the high frequency speaker part and both then are output synchronally. The high frequency speaker part and the low frequency speaker part can then be separated, in acoustic frequency, from each other. This will effectively solve the problem of intermodulation of distortion for the high and low acoustic frequencies, and reduce the size of the earphone to more compact.

Techniques for accurate, low-complexity, scalable indoor localization. Low-complexity anchor nodes generate acoustic beacon signals, which are passively detectable by a mobile device, which may be unmodified smartphones operating in an acoustic frequency range. The acoustic beacon signals are modulated via codes in a boundary band of audio and ultrasound frequencies, imperceptible to humans yet detectable via a voice microphone of an unmodified smartphone. An application on the mobile device passively captures the acoustic beacon signals and determines relative distances to the anchor nodes. Localization and distance update techniques, implemented on the mobile device and / or a remote server, determines and updates in real-time the location of the mobile device. The system may be scalable to support any number of mobile devices. Based on the tracked location, the indoor localization system may provide indoor location-based-services (LBS) to the mobile devices, and transmit to the mobile device information relevant to its location.

A method of detecting an event within a wellbore includes obtaining a sample data set, determining a plurality of frequency domain features of the sample data set, comparing the plurality of frequency domain features with an event signature, determining that the plurality of frequency domain features matches the thresholds, ranges, or both of the event signature, and determining the presence of the event within the wellbore based on determining that the plurality of frequency domain features match the thresholds, ranges, or both of the event signature. The sample data set is a sample of an acoustic signal originating within a wellbore including a fluid. The sample data set is representative of the acoustic signal across a frequency spectrum. The event signature includes a plurality of thresholds, ranges, or both corresponding to the plurality of frequency domain features.

A method for operating a beamforming microphone array for use in a predetermined area comprising: receiving acoustic audio signals at each of a plurality of microphones, converting the same to an electrical mic audio signal, and outputting each of the plurality of electrical mic audio signals; generating a user location data signal by a wave sensor system, and outputting the user location data signal, wherein the user location data signal includes location information of one or more people within the predetermined area; receiving both the user location data signal and plurality of mic audio signals at an adaptive beamforming device; adapting one or more beams by the adaptive beamforming device based on the user location data signal and plurality of output electrical mic audio signals wherein each of the one or more beams acquires sound from one or more specific locations in the predetermined area; and performing acoustic echo cancellation on each of the one or more beams output from the adaptive beamforming device.