AUDIO SYSTEM AND METHOD OF OPERATION THEREFOR

• US 20130272096A1
• Filed: 01/02/2012
• Published: 10/17/2013
• Est. Priority Date: 01/05/2011
• Status: Active Grant

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Koninklijke Philips N.V.
• Inventors: Pandharipande, Ashish Vijay, Srinivasan, Sriram
• Granted Patent: US 9,596,549 B2
• Time in Patent Office: Days
• US Class Current: 367/121
• CPC Class Codes: G01S 15/06 Systems determining the position data of a target
• CPC Class Codes: G01S 15/10 using transmission of interrupted, pulse-modulated waves determination of distance by phase measurement G01S15/32
• CPC Class Codes: G01S 7/521 Constructional features
• CPC Class Codes: G01V 1/001 Acoustic presence detection
• CPC Class Codes: G10K 11/348 using amplitude variation
• CPC Class Codes: H04M 3/56 Arrangements for connecting several subscribers to a common circuit, i.e. affording conference facilities video conference systems H04N7/15
• CPC Class Codes: H04R 1/403 loud-speakers
• CPC Class Codes: H04R 1/406 microphones
• CPC Class Codes: H04R 2400/01 Transducers used as a loudspeaker to generate sound aswell as a microphone to detect sound
• CPC Class Codes: H04R 2430/03 Synergistic effects of band splitting and sub-band processing
• CPC Class Codes: H04R 2430/20 Processing of the output signals of the acoustic transducers of an array for obtaining a desired directivity characteristic H04R2203/12 takes precedence
• CPC Class Codes: H04R 2499/11 Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's
• CPC Class Codes: H04R 2499/13 Acoustic transducers and sound field adaptation in vehicles
• CPC Class Codes: H04R 25/405 by combining a plurality of transducers
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04R 3/12 for distributing signals to two or more loudspeakers specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04S 2420/07 Synergistic effects of band splitting and sub-band processing
• CPC Class Codes: H04S 7/303 Tracking of listener position or orientation
• CPC Class Codes: H04S 7/305 Electronic adaptation of stereophonic audio signals to reverberation of the listening space H04S7/301 takes precedence

Abstract

An audio system comprises an ultrasound sensor array (105) which has a plurality of ultrasound sensor elements, and an audio band array (101) comprising a plurality of audio band elements. The same array of wideband audio transducers may be used for both the ultrasound sensor array (105) and the audio band array (101). An estimator (107) generates a presence characteristic of a user in response to ultrasound signals received from the ultrasound sensor array. The presence characteristic may specifically comprise a position estimate for the user. An audio array circuit (103) generates a directional response for the audio band array (101) by applying weights to individual audio band signals for the audio band elements. A weight circuit (109) determines the weights in response to the presence characteristic. The system may provide improved adaptation of the directivity of the audio band array (101) and specifically does not require the sound source in the audio band to be active for adaptation.

Claims

1. An audio system comprising:

an ultrasound transmitter arranged to transmit an ultrasound test signal;

an ultrasound sensor array comprising a plurality of ultrasound sensor elements;

an estimator for estimating a presence characteristic of a user in response to a comparison between a characteristic of the ultrasound test signal and a characteristic of the ultrasound signals received from the ultrasound sensor array;

an audio band array comprising a plurality of audio band elements;

an audio array circuit for generating a directional response of the audio band array by applying weights to individual audio band signals for the audio band elements; and

a weight circuit for determining the weights in response to the presence characteristic.

2. The audio system of claim 1 wherein the presence characteristic comprises a position estimate and the audio array circuit is arranged to determine the weights in response to the position characteristic.

3. The audio system of claim 1 wherein the audio band elements are audio sensors and the audio array circuit is arranged to generate a directional output signal by combining audio band signals from the audio sensors, the combining comprising applying the weights to the individual audio band signals.

4. The audio system of claim 3 comprising a plurality of wideband sensors each of which is both an ultrasound sensor of the ultrasound sensor array and an audio sensor of the audio band array.

5. The audio system of claim 4 wherein the plurality of wideband sensors forms both the ultrasound sensor array and the audio band array.

6. The audio system of claim 3 further comprising:

a user movement model arranged to track a position of a user;

an update circuit for updating the user movement model in response to both the ultrasound signals and the audio band signals.

7. The audio system of claim 6 wherein the update circuit is arranged to update the user movement model in response to the ultrasound signals when a characteristic of the audio band signals meets a criterion.

8. The audio system of claim 6 wherein the update circuit is arranged to not update the user movement model in response to the ultrasound signals when a characteristic of the audio band signals meets a criterion.

9. The audio system of claim 1 wherein the weight circuit is arranged to determine ultrasound weight delays for the ultrasound signals to correspond to a direction of an ultrasound source;

and to determine audio weight delays for the individual audio band signals to correspond to the ultrasound weight delays.

10. The audio system of claim 1 wherein the ultrasound sensor array and the audio band array are spatially overlapping.

12. The audio system of claim 8 wherein the ultrasound test signal is a pulsed ultrasound signal, and the estimator is arranged to perform a movement estimation in response to a comparison of signal segments of the ultrasound signals corresponding to different pulses.

13. The audio system of claim 12 wherein the estimator is arranged to estimate a position of a moving object in response to a difference between the signal segments.

14. The audio system of claim 1 wherein the audio band elements are audio drivers arranged to generate a sound signal in response to a drive signal, and the individual audio band signals are drive signals.

11. (canceled)

15. A method of operation for an audio system including an ultrasound sensor array comprising a plurality of ultrasound sensor elements and an audio band array comprising a plurality of audio band elements, the method comprising:

transmitting an ultrasound test signal;

estimating a presence characteristic of a user in response to a comparison between a characteristic of the ultrasound test signal and a characteristic of the ultrasound signals received from the ultrasound sensor array;

generating a directional response of an audio band array by applying weights to individual audio band signals for the audio band elements; and

determining the weights in response to the presence characteristic.