Estimating a room impulse response

Patent metadata

Field	Value
Publication number	US-9602923-B2
Application number	US-201314098283-A
Country	US
Kind code	B2
Filing date	Dec 5, 2013
Priority date	Dec 5, 2013
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

Various methods and systems for estimating a room impulse response between an audio source and an array of microphones are described. In one example, a method includes receiving audio signals at a microphone of an array of microphones. The audio signals correspond to each of the microphones in the array of microphones. The method also includes determining a room impulse response in a subspace that is compatible with a geometry of the array of microphones based on the received audio signals.

First claim

What is claimed is:

1. A method for estimating a room impulse response between an audio source and an array of microphones, comprising:
receiving audio signals at a microphone of an array of microphones, the audio signals corresponding to each of the microphones;
estimating a geometry of the array of microphones; and
determining a room impulse response in a subspace based on the estimated geometry of the array of microphones and the received audio signals, the received audio signals to be modeled based in part on a basis vector comprising a sampling interval, a propagation delay from the audio source to a center of the array of microphones, a channel length, an individual microphone from the array of microphones, and an angle of arrival from the received audio signals.

2. The method of claim 1 , comprising defining a set of single-source signals as the single-source signals would impinge on all microphones of the array of microphones at the same time, each of the single-source signals corresponding to a different location a single real or virtual source.

3. The method of claim 1 , comprising using the room impulse response to initialize an acoustic echo cancelation.

4. The method of claim 1 , comprising creating an approximation of the received audio signals as a weighted combination of the set of single-source signals.

5. The method of claim 4 , comprising using a sparse solver to determine a weight that satisfies a reconstruction error.

6. The method of claim 5 , wherein the weight is optimized utilizing convex optimization techniques.

7. The method of claim 5 , wherein the reconstruction error corresponds to modeling error plus noise.

8. The method of claim 1 , comprising calculating an impulse response in a subspace that is compatible with a microphone array geometry.

9. The method of claim 1 , wherein the received audio signals are represented by basis vectors; wherein the basis vectors are configured to represent real or virtual image signals that would be received by the microphone array from an unattenuated source.

10. The method of claim 1 , wherein the structure of the received signal is modeled by the following basis vector:

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Assignees

• Microsoft Corp
• Microsoft Technology Licensing Llc

Inventors

• Florencio Dinei
• Yellepeddi Atulya

Classifications

• G10K11/16 Primary

  Methods or devices for protecting against, or for damping, noise or other acoustic waves in general (G10K11/36 takes precedence) · CPC title

• H04M9/082

  using echo cancellers (echo cancellers per se H04B3/23) · CPC title

• H04M3/002

  Applications of echo suppressors or cancellers in telephonic connections (in two-way loud-speaking telephone systems H04M9/08, echo suppressors or cancellers per se H04B3/20) · CPC title

• H04R3/002

  Damping circuit arrangements for transducers, e.g. motional feedback circuits · CPC title

• H04R2227/007

  Electronic adaptation of audio signals to reverberation of the listening space for PA · CPC title