Electronic devices, methods, and computer program products for detecting noise in a signal based on autocorrelation coefficient gradients

• US 7,305,099 B2
• Filed: 08/12/2003
• Issued: 12/04/2007
• Est. Priority Date: 08/12/2003
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Ericsson Mobile Communications AB (Sony Group Corp.)
• Inventors: Gustavsson, Stefan
• Primary Examiner(s): Chin; Vivian
• Assistant Examiner(s): SUTHERS, DOUGLAS JOHN
• Application Number:
  US10/639,561
• Publication Number:
  US 20050038838A1
• Time in Patent Office: 1,575 Days
• Field of Search: 381/317, 381/318, 381/92, 381/94.1, 381/94.2, 381/94.3, 381/95, 381/91, 381/56, 381/58, 381 944- 948, 738/610.6, 702/191
• US Class Current: 381/317
• CPC Class Codes: G10L 2021/02163 Only one microphone
• CPC Class Codes: G10L 25/00 Speech or voice analysis techniques not restricted to a single one of groups G10L15/00 - G10L21/00 muting semiconductor-based amplifiers when some special characteristics of a signal are sensed by a speech detector, e.g. sensing when no signal is present, H03G3/34
• CPC Class Codes: H04R 2410/07 Mechanical or electrical reduction of wind noise generated by wind passing a microphone
• 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 25/453 electronically

Abstract

An electronic device can be operated to detect noise, such as wind noise. A microphone signal is generated by a microphone. Autocorrelation coefficients are determined based on the microphone signal. Gradient values are determined from the autocorrelation coefficients. The presence of a noise component in the microphone signal is determined based on the gradient values

Claims

1. A method of operating an electronic device, comprising:

generating a microphone signal by a microphone;

determining autocorrelation coefficients based on the microphone signal;

determining gradient values from the autocorrelation coefficients; and

determining presence of a noise component in the microphone signal based on an amount of variation of the gradient values over time.

2. The method of claim 1, wherein determining the presence of a noise component comprises determining the presence of wind noise in the microphone signal.

3. A method of operating an electronic device, comprising:

generating a microphone signal by a microphone;

determining autocorrelation coefficients based on the microphone signal;

determining gradient values from the autocorrelation coefficients; and

determining presence of a noise component in the microphone signal based on whether a rate of change of the gradient values satisfies a threshold value.

4. An electronic device, comprising:

a microphone that is configured to generate a microphone signal;

an autocorrelation unit that is configured to generate autocorrelation coefficients based on the microphone signal;

a gradient unit that is configured to generate gradient values from the autocorrelation coefficients; and

a wind detector that is configured to determine presence of a noise component in the microphone signal based on an amount of variation of the gradient values over time.

5. A computer program product configured to process a microphone signal produced by a microphone in an electronic device, comprising:

a computer readable storage medium having computer readable program code embodied therein, the computer readable program code comprising;

computer readable program code for determining autocorrelation coefficients based on the microphone signal;

computer readable program code for determining gradient values from the autocorrelation coefficients; and

computer readable program code for determining the presence of a noise component in the microphone signal based on an amount of variation of the gradient values over time.

6. The computer program product of claim 5, wherein:

the computer readable program code for determining autocorrelation coefficients comprises computer readable program code for generating sampled values of the microphone signal that are delayed by a range of delay values, and computer readable program code for generating autocorrelation coefficients based on the delayed sampled values of the microphone signal; and

the computer readable program code for determining the presence of the noise component comprises computer readable program code for determining whether the gradient values are about equal to a defined value for delay values that are substantially non-zero.

7. The computer program product of claim 6, wherein the computer readable program code for determining the presence of a noise component comprises computer readable program code for determining

whether the gradient values have a threshold crossing for delay values that are substantially non-zero.