SPEECH ENHANCEMENT SYSTEM

• US 20090287481A1
• Filed: 05/22/2009
• Published: 11/19/2009
• Est. Priority Date: 09/02/2005
• Status: Active Grant

• Current Assignee: Blackberry Limited
• Original Assignee: QNX Software Systems Limited (Canada) (Blackberry Limited)
• Inventors: Hetherington, Phillip A., Li, Xueman, Paranjpe, Shreyas
• Granted Patent: US 8,326,614 B2
• Time in Patent Office: Days
• US Class Current: 704/226
• CPC Class Codes: G10L 21/02 Speech enhancement, e.g. noise reduction or echo cancellation reducing echo effects in line transmission systems H04B3/20; echo suppression in hands-free telephones H04M9/08
• CPC Class Codes: G10L 21/0208 Noise filtering
• CPC Class Codes: H04B 1/66 for reducing bandwidth of signals; for improving efficiency of transmission H04B1/68 takes precedence
• CPC Class Codes: H04B 3/04 Control of transmission; Equalising
• CPC Class Codes: H04M 3/002 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

Abstract

A speech enhancement system improves speech conversion within an encoder and decoder. The system includes a first device that converts sound waves into operational signals. A second device selects a template that represents an expected signal model. The selected template models speech characteristics of the operational signals through a speech codebook that is further accessed in a communication channel.

Claims

1. A speech enhancement system, comprising:

a first device that converts sound waves into operational signals; and

A second device that selects one or more templates that represent spectral shapes and excitation pulses;

where the selected template models speech characteristics common to the operational signals through a speech codebook that further accessed in a communication channel.

2. The speech enhancement system of claim 1 further comprising a device selected from the group consisting of an adaptive filter, a spectral subtractor, a beam-former, a blind signal separation element, a de-correlation element, a de-convolution element, a parametric modeler, or a perceptual masker that processes the operational signal and has an output that affects the selection of the template of a speech Codec.

3. The speech enhancement system of claim 1 where the speech codebook comprises a shared codebook accessible to a remote third device that comprises an encoder and decoder.

4. The speech enhancement system of claim 1 where the first device and the second device comprises a unitary part of an enhanced variable rate Codec.

5. The speech enhancement system of claim 1 further comprising a spectral subtractor that reduces the noise that may distort a perceptual quality of a speech segment.

6. The speech enhancement system of claim 1 further comprising a switched beam beamformer in communication with the first device that combines signals received from a plurality of sensors that comprise an input array.

7. The speech enhancement system of claim 1 further comprising an adaptive beamformer in communication with the first device that automatically adapts to signals received from a plurality of sensors that comprise an input array.

8. The speech enhancement system of claim 1 further comprising an adaptive filter in communication with the first device that is configured to self-adjust its transfer function based on noise segments in the operational signals.

9. The speech enhancement system of claim 1 further comprising a blind source separator device in communication with the first device that is configured to separate a set of noisy segments from speech segments within the operational signals without the aid of information about the operational signals.

10. The speech enhancement system of claim 1 further comprising a blind source separator in communication with the first device configured to separate a set of noisy segments from the speech segments within the operational signals without the aid of information about the operating characteristics of the first device.

12. The speech enhancement system of claim 1 further comprising a decorrelation device in communication with the first device configured to reduce the correlation between speech segments and noise segments within the operational signals.

13. The speech enhancement system of claim 1 further comprising a deconvolution device in communication with the first device configured to reduce the correlation between speech segments and noise segments within the operational signals.

14. The speech enhancement system of claim 1 further comprising a parametric modeling device in communication with the first device configured to generate dimensional parameters of each of a plurality of noisy segments within the operational signals.

15. The speech enhancement system of claim 1 where the second device is configured to transmit as data set that retains a history of how the data was designed that updates down channel communication devices.

16. The speech enhancement system of claim 1 further comprising a perceptual masking device that substantially eliminates or minimizes noise.

17. The speech enhancement system of claim 1 further comprising a speech reconstruction controller in communication with the second device configured to reconstruct some or all of the attenuated harmonics of a speech segment.

18. A speech enhancement system, comprising:

a first device that converts sound waves into operational signals; and

a slave processor in communication with the first device that performs the specialized task of selecting a template that represents an expected signal model from a database based on characteristics of the operational signals;

where the selected template models speech characteristics through a speech codebook that further accessed in a communication channel; and

where the slave processor is subordinate to a controller resident to a Codec.

19. The speech enhancement system of claim 18 further comprising a blind source separator device in communication with the first device that is configured to separate a set of noisy segments from speech segments within the operational signals without the aid of information about the operational signals.

20. The speech enhancement system of claim 18 further comprising a deconvolution device in communication with the first device configured to reduce the correlation between speech segments and noise segments within the operational signals.