US4485484A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Directable microphone system
Assignee: Nokia Bell Labs
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Filing: 1982-10-28
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Granted: 1984-11-27
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Expires: 2002-10-28
Abstract
Abstract A microphone arrangement focuses on a prescribed volume in a large room such as an auditorium. The arrangement includes a plurality of directable beam microphone structures. Each beam is directed to a prescribed location. The signals produced in the microphone structures are selectively adjusted to accept sounds from a predetermined volume surrounding the location and to reject sounds outside the prescribed volume.
Inventors
- 👤 James L. Flanagan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:02
CPC Classifications
H; H04; H04R; H04R1/00; H04R1/20; H04R1/32; H04R1/40; H04R1/406; H04R3/00; H04R3/005; H04R2201/00; H04R2201/40; H04R2201/401
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
68 words
A signal processing arrangement for reducing audio interference in a reverberative environment comprising: a plurality of directable beam forming electroacoustic transducer means; means for steering the beam of each transducer means to a prescribed location in said environment; and means responsive to the output signals of said directable beam forming transducer means for forming a signal corresponding to sounds emanating from a predetermined volume surrounding said prescribed location.
Claim 2
Dependent Claim
68 words
A signal processing arrangement for reducing audio interference in a reverberative environment comprising: a plurality of directable beam forming electroacoustic transducer means; means for steering the beam of each transducer means to a prescribed location in said environment; and means responsive to the output signals of said directable beam forming transducer means for forming a signal corresponding to sounds emanating from a predetermined volume surrounding said prescribed location.
Claim 3
Dependent Claim
65 words
A signal processing arrangement for reducing audio interference in a reverberative environment according to claim 1 wherein each directable beam forming transducer means comprises: an array of spaced electroacoustic transducer elements each being adapted to generate a signal corresponding to sound waves incident thereon; and means responsive to the transducer element signals for generating a signal representative of sound waves within a prescribed beam pattern.
Claim 4
Dependent Claim
55 words
A signal processing arrangement for reducing audio interference in a reverberative environment according to claim 2 wherein said means for forming a signal corresponding to sounds emanating from a predetermined volume surrounding said prescribed location comprises means responsive to said prescribed beam pattern representative signals for adjusting the characteristics of each beam pattern representative signal.
Claim 5
Dependent Claim
40 words
A signal processing arrangement for reducing audio interference in a reverberative environment according to claim 3 wherein said adjusting means comprises means responsive to each beam pattern representative signal for reducing the phase differences between said beam pattern representative signals.
Claim 6
Dependent Claim
48 words
A signal processing arrangement for reducing audio interference in a reverberative environment according to claim 4 wherein said phase difference reducing means comprises means for rendering the phase characteristic of each beam pattern representative signal substantially similar to the phase characteristic of the other beam pattern representative signals.
Claim 7
Dependent Claim
81 words
A signal processing arrangement for reducing audio interference in a reverberative environment according to claim 5 wherein said beam pattern representative signal phase characteristic similarity rendering means comprises means for partitioning said beam pattern representative signal into a plurality of frequency bands, means responsive to each frequency band signal for generating a band representative signal having a prescribed phase characteristic, and means responsive to said band representative signals for forming a beam pattern representative signal replica having a predetermined phase characteristic.
Claim 8
Dependent Claim
29 words
A signal processing arrangement for reducing audio interference in a reverberative environment according to claim 6 wherein each beam pattern representative replica signal has substantially the same phase characteristic.
Claim 9
Dependent Claim
74 words
A signal processor for reducing audio interference in a reverberative environment comprising: first and second directable beam forming electroacoustic transducer means; means for directing the beams of the first and second transducer means to a pescribed location in said environment; and means for selectively adjusting the differences between the output signals of said first and second transducer means to generate a signal representative of sounds emanating from a prescribed volume surrounding said prescribed location.
Claim 10
Dependent Claim
74 words
A signal processor for reducing audio interference in a reverberative environment comprising: first and second directable beam forming electroacoustic transducer means; means for directing the beams of the first and second transducer means to a pescribed location in said environment; and means for selectively adjusting the differences between the output signals of said first and second transducer means to generate a signal representative of sounds emanating from a prescribed volume surrounding said prescribed location.
Claim 11
Dependent Claim
76 words
A signal processing arrangement for reducing audio interference in a reverberative environment according to claim 8 wherein each directable beam forming transducer means comprises: an array of regularly spaced electroacoustic transducer elements each being adapted to generate a signal corresponding to sound waves incident thereon; and means responsive to the transducer element signals, said transducer element spacing and the number of transducer elements for generating a signal representative of sound waves within a prescribed beam pattern.
Claim 12
Dependent Claim
62 words
A signal processing arrangement for reducing audio interference in a reverberative environment according to claim 9 wherein said difference adjusting means comprises: means responsive to said first transducer means output signal for generating a third signal having a predetermined phase characteristic; and means responsive to said second transducer means output signal for generating a fourth signal having substantially the same phase characteristic.
Claim 13
Dependent Claim
80 words
A signal processing arrangement for reducing audio interference in a reverberative environment according to claim 10 wherein each of said third and fourth signal generating means comprises: means for partitioning said transducer means output signal into a plurality of frequency bands, means responsive to each frequency band signal for generating a band representative signal having a prescribed phase characteristic, and means responsive to said band representative signals for forming a beam pattern representative signal replica having a predetermined phase characteristic.
Claim 14
Dependent Claim
49 words
A signal processing arrangement for reducing audio interference in a reverberative environment according to claim 11 wherein said reverberative environment is a room, said first transducer array is located on one wall of said room and said second transducer array is located on an adjacent wall of said room.
Claim 15
Independent Claim
85 words
A method of reducing audio interference in a reverberative environment having a plurality of directable beam electroacoustic transducers each including an array of spaced electroacoustic transducer elements each being adapted to generate a signal corresponding to sound waves incident thereon comprising the steps of: steering the beam of each directable beam transducer to a prescribed location in said environment; and forming a signal corresponding to sounds emanating from a predetermined volume surrounding said prescribed location responsive to the output signals of said directable beam transducers.
Claim 16
Independent Claim
85 words
A method of reducing audio interference in a reverberative environment having a plurality of directable beam electroacoustic transducers each including an array of spaced electroacoustic transducer elements each being adapted to generate a signal corresponding to sound waves incident thereon comprising the steps of: steering the beam of each directable beam transducer to a prescribed location in said environment; and forming a signal corresponding to sounds emanating from a predetermined volume surrounding said prescribed location responsive to the output signals of said directable beam transducers.
Claim 17
Dependent Claim
37 words
A method for reducing audio interference in a reverberative environment according to claim 13 wherein said signal formation comprises: generating a signal representative of sound waves within a prescribed beam pattern responsive to the transducer element signals.
Claim 18
Dependent Claim
50 words
A method for reducing audio interference in a reverberative environment according to claim 14 wherein forming a signal corresponding to sounds emanating from a predetermined volume surrounding said prescribed location further comprises adjusting the phase characteristics of each beam pattern representative signal responsive to said prescribed beam pattern representative signals.
Claim 19
Dependent Claim
37 words
A method for reducing audio interference in a reverberative environment according to claim 15 wherein said phase adjusting step comprises reducing the phase differences between said beam pattern representative signals responsive to each beam pattern representative signal.
Claim 20
Dependent Claim
43 words
A method for reducing audio interference in a reverberative environment according to claim 16 wherein said phase difference reducing comprises rendering the phase characteristic of each beam pattern representative signal substantially similar to the phase characteristic of the other beam pattern representative signals.
Claim 21
Dependent Claim
72 words
A method for reducing audio interference in a reverberative environment according to claim 17 wherein said beam pattern representative signal phase characteristic similarity rendering comprises partitioning said beam pattern representative signal into a plurality of frequency bands, generating a band representative signal having a prescribed phase characteristic responsive to each frequency band signal, and forming a beam pattern representative signal replica having a predetermined phase characteristic responsive to said band representative signals.
Claim 22
Dependent Claim
27 words
A method for reducing audio interference in a reverberative environment according to claim 18 wherein each beam pattern representative replica signal has substantially the same phase characteristic.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-11-27 | 1988-05-28 | 1988-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-11-27 | 1992-05-28 | 1992-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-11-27 | 1996-05-28 | 1996-11-27 | $7700.00 | Window Closed / Lapsed |