Patent US2188948A successfully refreshed from Google Patents.
Patent US5208864A successfully refreshed from Google Patents.
US5208864A
Expired / Lapsed
US
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Method of detecting acoustic signal
Assignee: NTT Inc
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Filing: 1990-03-08
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Granted: 1993-05-04
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Expires: 2010-03-08
Abstract
Abstract According to a method of detecting an acoustic signal, first and second sound receiving units are located at substantially the same position and are used to output signals having different target signal power to noise power ratios (S/N ratios). When a difference between the powers of the signals output from the first and second sound receiving units or a ratio of the power of the signal from the first sound receiving unit to that from the second sound receiving unit in a given period falls within a predetermined range, reception of the target signal within the given period is discriminated. The first sound receiving unit is an adaptive microphone array capable of controlling directivity characteristics in correspondence with a noise position.
Inventors
- 👤 Yutaka Kaneda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:14
CPC Classifications
G; G10; G10L; G10L25/00; G10L25/78; H; H04; H04R; H04R3/00; H04R3/005; G10L21/00; G10L21/02; G10L21/0208; G10L2021/02082; G10L21/0216; G10L2021/02161; G10L2021/02166; H04R2201/00; H04R2201/40; H04R2201/403
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
103 words
A method of detecting an acoustic signal, comprising the steps of: using first and second sound receiving units, located at the same position and having different directivity characteristics, for outputting signals having different target signal power to noise power ratios; and when a difference between logarithmic powers of said signals output from said first and second sound receiving units in a given period falls within a predetermined range, determining reception of the target signal within the given period, and using said first sound receiving unit in the form of an adaptive microphone array for controlling directivity characteristics in correspondence with a noise position.
Claim 2
Independent Claim
103 words
A method of detecting an acoustic signal, comprising the steps of: using first and second sound receiving units, located at the same position and having different directivity characteristics, for outputting signals having different target signal power to noise power ratios; and when a difference between logarithmic powers of said signals output from said first and second sound receiving units in a given period falls within a predetermined range, determining reception of the target signal within the given period, and using said first sound receiving unit in the form of an adaptive microphone array for controlling directivity characteristics in correspondence with a noise position.
Claim 3
Dependent Claim
49 words
The method according to claim 1, wherein said first sound receiving unit comprises a microphone array having a plurality of microphone elements, and a directivity controller connected to a plurality of outputs of said microphone array, and wherein said second sound receiving unit includes one of said microphone elements.
Claim 4
Dependent Claim
79 words
A method according to claim 1, further comprising the step of: when the difference between the logarithmic powers of said signals output from said first and second sound receiving units in a given period falls within a predetermined range and a power of the signal output from a sound receiving unit having a higher signal power to noise power ratio in the given period falls within a predetermined range, discriminating reception of the target signal within the given period.
Claim 5
Dependent Claim
72 words
The method according to claim 1, wherein said first sound receiving unit comprises a microphone array constituted by a plurality of microphone elements, and a directivity controller connected to a plurality of outputs of said microphone array; and said second sound receiving unit comprises some of the microphone elements constituting said microphone array serving as said first sound receiving unit and a directivity synthesizer connected to said some of said microphone elements.
Claim 6
Dependent Claim
50 words
A method according to claim 1, further comprising the step of discriminating that the target signal is received in the given period only when the period in which it is determined that the target signal has been received as described exceeds an expected minimum continuous duration of said target signal.
References Cited (Backward Citations)
US4195360A
Cited
US4215241A
Cited
US4412097A
Cited
US4559642A
Cited
GB2128054A
Cited
US4536887A
Cited
US4696043A
Cited
US4589137A
Cited
US4653102A
Cited
US4888807A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-05-03 | 1996-11-02 | 1997-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-05-03 | 2000-11-02 | 2001-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-05-03 | 2004-11-02 | 2005-05-04 | $7700.00 | Window Closed / Lapsed |