Methods and systems for spatial filtering transmitters and receivers capable of simultaneous communication with one or more receivers and transmitters, respectively, the receivers capable of outputting source directions to humans or devices. The methods and systems use spherical wave field partial wave expansion (PWE) models for transmitted and received fields at antennas and for waves generated by contributing sources. The source PWE models have expansion coefficients expressed as functions of directional coordinates of the sources. For spatial filtering receivers a processor uses the output signals from at least one sensor outputting signals consistent with Nyquist criteria representative of the wave field and the source PWE model to determines directional coordinates of sources (wherein the number of floating point operations are reduced) and outputs the directional coordinates and communications to a reporter configured for reporting information to humans. For spatial filtering transmitters a processor uses known receiver directions and source partial wave expansions to generate signals for transducers producing a composite total wave field conveying communications to the specified receivers. The methods and communications reduce the processing required for transmitting and receiving spatially filtered communications.

Provided are a device control method and apparatus. The method is applied to an audio device, and includes: receiving an acoustic signal set, determining a propagation characteristic of an acoustic signal in the acoustic signal set, determining, according to the propagation characteristic, a device parameter associated with audio play quality to be used by the audio device, and controlling the audio device to play audio with the device parameter.

Provided are a device control method and apparatus. The method is applied to an audio device, and includes: receiving an acoustic signal set, determining a propagation characteristic of an acoustic signal in the acoustic signal set, determining, according to the propagation characteristic, a device parameter associated with audio play quality to be used by the audio device, and controlling the audio device to play audio with the device parameter.

An acoustic system and method detect and locate low intensity and low frequency sound sources in an investigation area. An acoustic system is effective in identifying survivors trapped under rubble following a catastrophic event. The acoustic system focuses on the low frequency components of the human voice and includes acoustic sensors for detecting acoustic signals generated by the sound sources and for generating data representative of the acoustic signals. A wireless transmitter transmits the data representative of the detected acoustic signals to an electronic receiver block that receives and analyzes the data. A processor executes calibration of the acoustic sensors of the suite to temporally align each signal received from the acoustic sensors, and executes a digital beamforming to combine the data representative of the detected acoustic signals and to create an acoustic image of the investigation area to locate the low intensity and low frequency sound sources.

An acoustic system and method detect and locate low intensity and low frequency sound sources in an investigation area. An acoustic system is effective in identifying survivors trapped under rubble following a catastrophic event. The acoustic system focuses on the low frequency components of the human voice and includes acoustic sensors for detecting acoustic signals generated by the sound sources and for generating data representative of the acoustic signals. A wireless transmitter transmits the data representative of the detected acoustic signals to an electronic receiver block that receives and analyzes the data. A processor executes calibration of the acoustic sensors of the suite to temporally align each signal received from the acoustic sensors, and executes a digital beamforming to combine the data representative of the detected acoustic signals and to create an acoustic image of the investigation area to locate the low intensity and low frequency sound sources.

A method for calibrating an acoustic antenna including elementary transducers distributed over an antenna row or plane, about a reference transducer, the antenna defining a main axis, passing through the reference transducer, and perpendicular to the antenna row or plane, the method including: measuring signals generated by elementary transducers in response to a calibration acoustic wave from a calibration source; on the basis of these measurements, determining a temporal phase shift of the signal respectively generated by each elementary transducer; reiterating the above steps in such a way that, in at least one iteration, the position of the calibration source may be considered to be centered on the main axis; and estimating a phase shift of each elementary transducer with respect to the reference transducer.

A beamforming system comprises an input module, a phase-difference module, a delay distribution module, and a delay estimation module configured to make a final delay estimation based on the delay distribution. The final delay estimation is applied to align one of two selected channels and combine the two channels to obtain a signal of interest. The phase-difference module calculates phase differences for a range of frequency bins. The delay estimation module considers all possible delays derived from the phase differences, including multiples of ±2π to overcome the ambiguity in high frequency bins when the spacing between two acoustic sensors is longer than the half of the wavelengths.

A beamforming system comprises an input module, a phase-difference module, a delay distribution module, and a delay estimation module configured to make a final delay estimation based on the delay distribution. The final delay estimation is applied to align one of two selected channels and combine the two channels to obtain a signal of interest. The phase-difference module calculates phase differences for a range of frequency bins. The delay estimation module considers all possible delays derived from the phase differences, including multiples of ±2π to overcome the ambiguity in high frequency bins when the spacing between two acoustic sensors is longer than the half of the wavelengths.

In accordance with an embodiment a package includes: a package structure which defines inner surfaces delimiting an inner volume and outer surfaces directed towards an exterior of the package; at least one acoustic sensor element applied to at least one of the inner surfaces, to convert acoustic waves arriving from the exterior of the package into acoustic information in the form of electric signals; a plurality of millimeter wave sensing elements applied to at least one of the outer surfaces, to receive reflected radar signals from objects in the exterior of the package; and a circuitry applied to at least one of the inner surfaces of the package structure, wherein the circuitry is electrically connected to the at least one acoustic sensor element and the plurality of millimeter wave sensing elements to process the acoustic information and the reflected radar signals.

An acoustic system and method detect and locate low intensity and low frequency sound sources in an investigation area. An acoustic system is effective in identifying survivors trapped under rubble following a catastrophic event. The acoustic system focuses on the low frequency components of the human voice and includes acoustic sensors for detecting acoustic signals generated by the sound sources and for generating data representative of the acoustic signals. A wireless transmitter transmits the data representative of the detected acoustic signals to an electronic receiver block that receives and analyzes the data. A processor executes calibration of the acoustic sensors of the suite to temporally align each signal received from the acoustic sensors, and executes a digital beamforming to combine the data representative of the detected acoustic signals and to create an acoustic image of the investigation area to locate the low intensity and low frequency sound sources.