Dynamic Gain Adjustment Based on Signal to Ambient Noise Level

• US 20120076311A1
• Filed: 03/30/2011
• Published: 03/29/2012
• Est. Priority Date: 09/28/2010
• Status: Active Grant

• Current Assignee: Bose Corporation
• Original Assignee: Bose Corporation
• Inventors: Isabelle, Steven H., Iyengar, Vasu
• Granted Patent: US 8,798,278 B2
• Time in Patent Office: Days
• US Class Current: 381/57
• CPC Class Codes: G10L 21/0208 Noise filtering
• CPC Class Codes: H04R 1/086 Protective screens, e.g. all weather or wind screens
• CPC Class Codes: H04R 2410/07 Mechanical or electrical reduction of wind noise generated by wind passing a microphone

Abstract

Methods and apparatuses for deriving a signal-to-noise ratio based at least in part on a measured level of a signal carrying far-end speech, and a measured level of a signal carrying ambient acoustic noise; determining a target gain adjustment based at least in part on the derived signal-to-noise ratio; applying the target gain adjustment to the signal carrying far-end speech to produce a gain-adjusted signal; and providing the gain-adjusted signal for audio output from a communications device.

Claims

1. A method comprising:

deriving a signal-to-noise ratio based at least in part on a measured level of a signal carrying far-end speech, and a measured level of a signal carrying ambient acoustic noise;

determining a target gain adjustment based at least in part on the derived signal-to-noise ratio;

applying the target gain adjustment to the signal carrying far-end speech to produce a gain-adjusted signal; and

providing the gain-adjusted signal for audio output from a communications device.

2. The method of claim 1, wherein the communications device comprises a wireless in-ear headset.

3. The method of claim 1, wherein the signal-to-noise ratio is further derived based in part on a user-selected gain adjustment.

4. The method of claim 3, wherein the user-selected gain adjustment is provided via a user-operable gain controller component of the communications device.

5. The method of claim 1, wherein the target gain adjustment is further determined based in part on a mapping of signal-to-noise ratio to gain in which the mapping approaches a unity gain (0 dB) at high signal-to-noise ratios and has a negative slope of nonincreasing magnitude as the signal-to-noise ratios increase from low to high.

6. The method of claim 5, wherein the mapping is expressed as a gain curve.

7. A communications device comprising:

first circuitry operable to derive a signal-to-noise ratio based at least in part on a measured level of a signal carrying far-end speech, and a measured level of a signal carrying ambient acoustic noise;

second circuitry operable to determine a target gain adjustment based at least in part on the derived signal-to-noise ratio; and

third circuitry operable to apply the target gain adjustment to the signal carrying far-end speech to produce a gain-adjusted signal and provide the gain-adjusted signal for output from the device.

8. The device of claim 7, further comprising:

an electronics module to wirelessly receive audio signals carrying far-end speech and wirelessly transmit audio signals carrying near-end speech.

9. The device of claim 7, further comprising:

an audio module including an acoustic driver to transduce audio signals to acoustic energy.

10. The device of claim 7, wherein the device comprises an in-ear component that includes:

an outlet section dimensioned and arranged to fit inside an ear canal of a user; and

a passageway to conduct acoustic energy from an audio module to an opening in the outlet section.

11. The device of claim 7, further comprising:

an electronics module including a microphone having multiple acoustic ports.

12. The device of claim 11, wherein the microphone has two acoustic ports with a center-to-center spacing of approximately 6.5 mm.

13. The device of claim 11, further comprising:

a porous member arranged over the microphone to reduce wind noise.