Integrated sound input system

• US 20030033144A1
• Filed: 06/13/2002
• Published: 02/13/2003
• Est. Priority Date: 08/08/2001
• Status: Abandoned Application

• Current Assignee: Apple Inc.
• Original Assignee: Apple Computer Incorporated (Apple Inc.)
• Inventors: Neeracher, Matthias U., Cerveau, Laurent J., Silverman, Kim E.
• Application Number:
  US10/172,593
• Publication Number:
  US 20030033144A1
• Time in Patent Office: Days
• US Class Current: 704/233
• CPC Class Codes: G10L 15/20 Speech recognition techniques specially adapted for robustness in adverse environments, e.g. in noise, of stress induced speech G10L21/02 takes precedence
• CPC Class Codes: G10L 2021/02165 Two microphones, one receiving mainly the noise signal and the other one mainly the speech signal
• CPC Class Codes: G10L 2021/02166 Microphone arrays; Beamforming

Abstract

A method for speech recognition is provided. Generally, a first signal is generated from a first microphone. The first signal is transformed to coefficients. The coefficients from the first signal are inputted to a multiple channel noise rejection device. A second signal is generated from a second microphone. The second signal is transformed to coefficients. The coefficients from the second signal are inputted to the multiple channel noise rejection device. Coefficients from the multiple channel noise rejection device, which are dependent on coefficients from the first signal and coefficients from the second signal, are provided to an acoustic model selector. Acoustic model hypotheses are chosen based on the coefficients from the multiple channel noise rejection device.

Claims

1. A speech recognition device, comprising:

a first microphone, which generates a first signal;

a second microphone, which generates a second signal;

a multiple channel noise rejection device connected to the first microphone and the second microphone, wherein the multiple channel noise rejection device combines output from the first signal and the second signal and generates coefficients related to the first signal and the second signal;

an acoustic model selector, which is able to receive the coefficients from the multiple channel noise rejection device;

a coefficient database connected to the acoustic model selector; and

an acoustic model database connected to the acoustic model selector.

2. The speech recognition device, as recited in claim 1, wherein the acoustic model selector compares coefficients received from the multiple channel noise rejection device with coefficients in the database and with the acoustic model database to obtain acoustic model hypotheses.

3. The speech recognition device, as recited in claim 2, further comprising:

a first Fast Fourier Transform device connected between the first microphone and the multiple channel noise rejection device; and

a second Fast Fourier Transform device connected between the second microphone and the multiple channel noise rejection device.

4. The speech recognition device, as recited in claim 3, further comprising:

a back end connected to the acoustic model selector; and

a language model database connected to the back end.

5. The speech recognition device, as recited in claim 4, wherein the back end receives acoustic model hypotheses from the acoustic model selector and compares the acoustic model hypotheses with data in the language model database.

6. The speech recognition device, as recited in claim 5, wherein the first microphone, second microphone, first Fast Fourier Transform device, second Fast Fourier Transform device, and multiple channel noise rejection device form a communications device, and wherein the acoustic model selector, coefficient database, acoustic model database form a server device.

7. The speech recognition device, as recited in claim 6, wherein the multiple channel noise rejection device is tailored for characteristics of the first microphone and the second microphone.

8. A method for providing speech recognition, comprising the steps of:

generating a first signal from a first microphone;

transforming the first signal to coefficients;

inputting the coefficients from the first signal to a multiple channel noise rejection device;

generating a second signal from a second microphone;

transforming the second signal to coefficients;

inputting the coefficients from the second signal to the multiple channel noise rejection device;

providing coefficients from the multiple channel noise rejection device, which are dependent on coefficients from the first signal and coefficients from the second signal, to an acoustic model selector; and

choosing acoustic model hypotheses based on the coefficients from the multiple channel noise rejection device.

9. The method, as recited in claim 8, further comprising the step of choosing a command from a language model database based on the acoustic model hypotheses.