30 results about "Parametric loudspeaker" patented technology

A virtual headset for enabling isolated listening to audio material by a listener without need for earphones or other physical audio producing devices attached to the listener. The virtual headset includes a parametric ultrasonic signal source 504 supplying at least a first parametric ultrasonic channel signal comprised of an ultrasonic carrier signal and at least one sideband, and configured to be emitted and directed substantially exclusively at a first ear 506 of the listener 502. The parametric ultrasonic signal source is coupled to an electro-acoustical emitter structure, which is configured to emit and direct a first parametric ultrasonic wave corresponding to the first parametric ultrasonic channel signal at the listener such that a first resultant decoupled audio wave will be heard substantially exclusively at the first ear of the listener, with minimal audible sound at a second ear 514 of the listener.

A sound reproducing device includes parametric speakers disposed to a display, a loudspeaker, drivers, a human-body sensor, and a controller. The loudspeaker has a wider directivity than the parametric speakers. The drivers change directions of the parametric speakers, respectively. The parametric speakers and the drivers constitute at least two parametric speaker units each composed of respective one of the parametric speakers and respective one of the drivers. The controller reproduces sound information based the number of persons in front of the display detected from an output from the human-body senor. The sound reproducing device reduces the possibility for a number of persons to hear the sound noisily, and allows drawing more attention to the content, e.g. an advertisement.

A system for providing audio information to persons in an approach path (12) includes an interaction point (14), and an approach path (12) leading to the interaction point. A parametric sound system (18) is provided, which includes a parametric speaker (20) disposed adjacent to the interaction point. The parametric sound system is configured for limited delivery of sound in a spatially limited audio zone (24) along the approach path (12), within a decibel level above ambient noise levels in the area of the interaction point (14), and sufficiently high to be heard primarily by a person progressing along the approach path (12). The interaction point can be a cashier station, and the system can also include a video display (16) configured to provide video information to persons in the approach path along with the audio information.

A method and system for generating parametric output directly from a prerecorded and error corrected parametric signal for playback in a parametric loudspeaker system. The method includes the step of retrieving a pre-encoded audio signal from an electronically readable storage medium. In addition, an ultrasonic carrier signal has at least one sideband which represents the pre-encoded audio signal. The next step is playing back the pre-encoded audio signal through an ultrasonic amplifier and emitter.

A method is disclosed for increasing a parametric output of a parametric loudspeaker system. The method can include the operation of providing multiple ultrasonic frequency emission zones that output signals in a frequency band. The phase relationships of the ultrasonic frequency emission zones can be correlated and controlled to increase phase coherence between each ultrasonic frequency emission zone to maximize parametric output. Correlating and controlling the phase relationships can include offsetting a frequency of a carrier signal applied to each emission zone from a resonant frequency of each emission zone in view of a rate of change of phase of each emission zone in a vicinity of each resonant frequency. Ultrasonic energy from the ultrasonic frequency emission zones can be generated, using the correlated phase relationship to increase the parametric output.

A parametric loudspeaker system and method for reducing distortion in a decoupled audio wave by creating a double sideband parametric ultrasonic signal that substantially approximates a non-square-rooted modulation envelope and emitting a parametric ultrasonic wave that corresponds to the double sideband parametric ultrasonic signal from a parametric loudspeaker at a sufficient amplitude to drive the surrounding air into saturation.

An alarm clock is mounted above a bed and uses a thermal sensor to identify the location of each person sleeping in the bed and to direct light and sound to only one of them for the purpose of selectively waking only that individual. A platform is driven to scan across the bed, and has an infrared sensor creating a temperature profile with a thermal signature indicating the position of each occupant. Platform electronics generate a narrow beam LED light, and an array of ultrasonic speakers serves as a parametric speaker producing a narrow sound beam heard only by the targeted sleeper. At a preset time the alarm is triggered and the platform is pointed at the targeted sleeper identified by his or her infrared thermal signature. The LED light is driven from low to high to simulate dawn. Following maximum brightness, the parametric speaker emits a wake-up audio.

An acoustic sound system usable in electronic entertainment systems that generates highly directional sound. The directed acoustic sound system includes a parametric audio sound system having a modulator for modulating an ultrasonic carrier signal with a processed audio signal, a driver amplifier for amplifying the modulated signal, and a parametric loudspeaker for projecting the modulated and amplified signal through the air for subsequent regeneration of the audio signal along a pre-selected path. The acoustic sound system allows a user to select the parametric loudspeaker, a connectable non-directional loudspeaker, or both loudspeakers for producing audible sound. The acoustic sound system may be employed in the home, in the workplace, or in any other environment where audio leakage is undesirable.

A parametric loudspeaker system comprises a pre-compensator (305) for generating a pre-compensated envelope signal by applying a pre-compensation to the input audio signal where the pre-compensation compensates for distortion of in-air demodulation of the modulated ultrasound signal. A pre-modulator (307) generates a complex base band signal generating a phase signal from the pre-compensated envelope signal using a predetermined function for determining a phase signal from an amplitude signal such that the corresponding complex signal has either suppressed negative or positive frequencies. The complex base band signal is then generated to have an amplitude corresponding to the pre-compensated envelope signal and a phase corresponding to the phase signal. A modulator (309) quadrature modulates the complex base band signal on an ultrasonic quadrature carrier and an output circuit (311) drives the ultrasound transducer (301) from the modulated signal. The invention may allow effective yet low resource pre-compensation for a suppressed or single sideband modulated modulated ultrasound signal.

A method for minimizing the reactance of a reactive load transducer at a carrier frequency in an amplifier with a power output stage for amplifying a signal, comprises: supplying a signal to the power output stage of the amplifier which includes at least one reactive component coupled to the amplifier; and counteracting transducer reactance at a carrier frequency by interacting the signal with the at least one reactive component.

A parametric loudspeaker system comprises a pre-compensator (305) for generating a pre-compensated envelope signal by applying a pre-compensation to the input audio signal where the pre-compensation compensates for distortion of in-air demodulation of the modulated ultrasound signal. A pre-modulator (307) generates a complex base band signal generating a phase signal from the pre-compensated envelope signal using a predetermined function for determining a phase signal from an amplitude signal such that the corresponding complex signal has either suppressed negative or positive frequencies. The complex base band signal is then generated to have an amplitude corresponding to the pre-compensated envelope signal and a phase corresponding to the phase signal. A modulator (309) quadrature modulates the complex base band signal on an ultrasonic quadrature carrier and an output circuit (311) drives the ultrasound transducer (301) from the modulated signal. The invention may allow effective yet low resource pre-compensation for a suppressed or single sideband modulated modulated ultrasound signal.

A sound reproducing device includes parametric speakers disposed to a display, a loudspeaker, drivers, a human-body sensor, and a controller. The loudspeaker has a wider directivity than the parametric speakers. The drivers change directions of the parametric speakers, respectively. The parametric speakers and the drivers constitute at least two parametric speaker units each composed of respective one of the parametric speakers and respective one of the drivers. The controller reproduces sound information based the number of persons in front of the display detected from an output from the human-body senor. The sound reproducing device reduces the possibility for a number of persons to hear the sound noisily, and allows drawing more attention to the content, e.g. an advertisement.

A sound reproducing device includes parametric speakers disposed to a display, a loudspeaker, drivers, a human-body sensor, and a controller. The loudspeaker has a wider directivity than the parametric speakers. The drivers change directions of the parametric speakers, respectively. The parametric speakers and the drivers constitute at least two parametric speaker units each composed of respective one of the parametric speakers and respective one of the drivers. The controller reproduces sound information based the number of persons in front of the display detected from an output from the human-body senor. The sound reproducing device reduces the possibility for a number of persons to hear the sound nosily, and allows drawing more attention to the content, e.g. an advertisement.

A parametric loudspeaker system comprises a pre-compensator (305) for generating a pre-compensated envelope signal by applying a pre-compensation to the input audio signal where the pre-compensation compensates for distortion of in-air demodulation of the modulated ultrasound signal. A pre-modulator (307) generates a complex base band signal generating a phase signal from the pre-compensated envelope signal using a predetermined function for determining a phase signal from an amplitude signal such that the corresponding complex signal has either suppressed negative or positive frequencies. The complex base band signal is then generated to have an amplitude corresponding to the pre-compensated envelope signal and a phase corresponding to the phase signal. A modulator (309) quadrature modulates the complex base band signal on an ultrasonic quadrature carrier and an output circuit (311) drives the ultrasound transducer (301) from the modulated signal. The invention may allow effective yet low resource pre-compensation for a suppressed or single sideband modulated modulated ultrasound signal.

Disclosed is an electronic device including: a housing (110) in which at least one sound hole (113) and at least one sound hole (114) are formed; an oscillator (120) that is provided inside the housing (110) and outputs a modulated wave for a parametric loudspeaker; a sound demodulation unit (130) that is not provided in the sound hole (113) but provided in the sound hole (114) and demodulates the modulated wave; and a sound hole opening and closing unit (112) that is mounted to the housing (110) and opens and closes the sound hole (113).

In one embodiment of the present invention, a loudspeaker modeling subsystem configures a neural lumped parameter loudspeaker (NeLP) model to represent the behavior of a loudspeaker. The NeLP model is implemented as a cascaded combination of a lumped parameter model (LPM) and a neural network (NN) model. To configure the model, the loudspeaker modeling subsystem first estimates values for the parameters used in the LPM. The loudspeaker modeling subsystem then “fixes” these parameters and trains the NN model to act on a predicted output pressure that is generated via the LPM. More specifically, the loudspeaker modeling subsystem configures the NN to modify the predicted output pressure to minimize the error between the predicted output pressure and a measured loudspeaker output pressure. Notably, by strategically fusing the LPM and the NN model, the NeLP model leverages the strengths and mitigates the weaknesses typically associated with conventional loudspeaker modeling techniques.

The present invention relates to a sound zone control device and method in a vehicle, a controller and a medium. The device includes a main control module, a power amplifier module and a plurality of directional transmission modules. There is a channel between the power amplifier module and each directional transmission module. The transmission module corresponds to a sound area in the car; the main control module is configured to determine the channel to be sent by the audio signal, obtain the channel number to be sent, and send the channel number and the audio signal to the power amplifier module; the power amplifier module is configured to transmit the audio signal The signal is amplified by a preset multiple, and the amplified audio signal is sent to the directional transmission module corresponding to the channel number to be sent; the directional transmission module is configured to directional transmit the amplified audio signal to the corresponding sound area. Based on the strong directivity of the parametric loudspeaker, the invention realizes the directional transmission of the sound, so that the driver and passengers in the car only receive the sound related to it, which is simple and easy to implement, has strong adaptability to the whole vehicle environment, and has wider and more flexible applications.