Speakerphone and/or microphone arrays and methods and systems of using the same

• US 20110194719A1
• Filed: 11/12/2010
• Published: 08/11/2011
• Est. Priority Date: 11/12/2009
• Status: Active Grant

• Current Assignee: Robert Henry Frater
• Original Assignee: Robert Henry Frater
• Inventors: Frater, Robert Henry
• Granted Patent: US 9,113,264 B2
• Time in Patent Office: Days
• US Class Current: 381/332
• CPC Class Codes: G10L 2021/02082 the noise being echo, reverberation of the speech
• CPC Class Codes: G10L 2021/02166 Microphone arrays; Beamforming
• CPC Class Codes: G10L 21/0232 Processing in the frequency domain
• CPC Class Codes: H04R 1/02 Casings; Cabinets ; Supports therefor; Mountings therein H04R1/28 takes precedence ; attachments for microphones H04R1/08; mounting of transducers in earpieces H04R1/1075
• CPC Class Codes: H04R 1/406 microphones
• CPC Class Codes: H04R 2201/401 2D or 3D arrays of transducers
• CPC Class Codes: H04R 2201/403 Linear arrays of transducers
• CPC Class Codes: H04R 2227/001 Adaptation of signal processing in PA systems in dependence of presence of noise
• CPC Class Codes: H04R 2227/007 Electronic adaptation of audio signals to reverberation of the listening space for PA
• CPC Class Codes: H04R 2410/01 Noise reduction using microphones having different directional characteristics
• CPC Class Codes: H04R 2430/25 Array processing for suppression of unwanted side-lobes in directivity characteristics, e.g. a blocking matrix
• CPC Class Codes: H04R 2499/11 Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's
• CPC Class Codes: H04R 27/00 Public address systems circuits for preventing acoustic reaction H04R3/02; circuits for distributing signals to loudspeakers H04R3/12; monitoring or testing arrangements for public address systems H04R29/007; amplifiers H03F
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407

Abstract

The present disclosure is directed to devices, methods and systems for microphone arrays wherein enhancing performance of directional microphone arrays is provided. Enhanced performance of speaker phones is also provided. In certain embodiments, the housing of the device is configured to support the at least three microphones and the loudspeaker in a substantially first orientation; and the at least three microphones and the loudspeaker are arranged in a spatial relationship such that appropriate phase and delay characteristics achieve a substantial null response in the at least three microphones and in the loudspeaker in a substantial vertical direction away from the substantially first orientation over a desired audible range of frequencies and the device is able to provide a response to sounds over a range of first oriented elevations.

Claims

1-21. -21. (canceled)

22. A device, comprising:

at least three microphone elements;

at least one loudspeaker;

at least one housing, wherein the at least one housing is configured to support the at least three microphone elements in a first orientation and the at least one loudspeaker in a second orientation; and

the at least three microphones are arranged with appropriate phase and delay characteristics to achieve a substantial null response in positions having a substantially equal sound path from the at least three microphone elements over a desired audible range of frequencies; and

the device is able to provide a response to sounds over a range of second oriented elevations away from the first orientation containing the at least three microphone elements; and

the uncompensated response of the device falls off at a multiple of 6 dB per octave from high to low frequencies.

23. A device as in claim 22, wherein the at least three microphone elements are substantially equispaced in a circular arrangement with relative phases 0°

, 360°

/n, 2×

360°

/n up to (n−

1)×

360°

/n over the desired frequency range and the at least one loudspeaker is placed substantially below the at least three microphone elements in a position having substantially equal sound paths to each of the at least three microphone elements.

24. A device as in claim 23, wherein the at least three microphone elements are substantially equispaced in a circular arrangement in a substantially horizontal planar configuration.

25. A device as in claim 24, wherein a Hilbert network is used to provide the relative phasing for the microphone elements over the desired bandwidth.

26. A device as in claim 25, wherein there are four microphone elements

27. A device as in claim 22, wherein the at least three microphone elements are substantially equispaced in a first circular arrangement and the first circular arrangement has a first diameter and each microphone element has a relative phase 0°

; and

the device further comprises a second at least three microphone elements which are substantially equispaced in a second circular arrangement with a second diameter and each microphone element has a relative phase 180°

;

wherein the first diameter is greater than the second diameter.

28. A device as in claim 27, wherein the at least three microphone elements in the first circular arrangement are in a substantially horizontal planar configuration.

29. A device as in claim 27, wherein the second at least three microphone elements in the second circular arrangement are in a substantially horizontal planar configuration.

30. A device as in claim 27, wherein the at least three microphone elements in the first circular arrangement are in a substantially horizontal planar configuration, and the second at least three microphone elements are in a substantially horizontal planar configuration.

31. A device as in claim 22 where the at least one loudspeaker is arranged such that the loudspeaker is disposed in a zone of insensitivity of the at least three microphone elements and radiates sound away from the at least three microphone elements and towards a surface upon or against which the housing is abutted, such as a desktop or a vertical wall surface and the at least one loudspeaker has a sound radiation axis that is disposed generally perpendicularly to the abutting surface.

32. A device as in claim 22, wherein the at least three microphone elements are arranged to achieve at least one axis of sensitivity defining a zone of microphone sensitivity, and at least one axis of insensitivity defining a zone of insensitivity of the at least three microphone elements over the 300 Hz to 3.3 KHz frequency range.

33. A device as in claim 22, wherein the at least three microphone elements are arranged to achieve at least one axis of sensitivity defining a zone of microphone sensitivity, and at least one axis of insensitivity defining a zone of insensitivity of the at least three microphone elements over the 300 Hz to 3.3 KHz frequency range;

and wherein the at least one loudspeaker is arranged relative to the at least three microphone elements so that the audio from the at least one loudspeaker is also substantially cancelled by the at least three microphone elements in the at least one axis of insensitivity defining a zone of insensitivity of the at least one loudspeaker over the 300 Hz to 3.3 KHz frequency range.

34. A device comprising:

at least one loudspeaker;

at least two bi-directional microphone elements;

at least one housing wherein the at least one housing is configured to support the at least one loudspeaker and the at least two bi-directional microphone elements; and

the at least two bidirectional microphone elements are configured to provide appropriate phase and delay characteristics so as to achieve at least one axis of sensitivity defining a zone of microphone sensitivity, and at least one axis of insensitivity defining a zone of insensitivity of the microphone over a first desired audible range of frequencies; and

wherein the at least one loudspeaker is configured relative to the at least two bi-directional microphone elements so that the audio from the loudspeaker is substantially cancelled by the at least two bi-directional microphone elements in the at least one axis of insensitivity defining a zone of insensitivity of the loudspeaker over a second desired audible range of frequencies.

35. A device as in claim 34 wherein, a Hilbert Network is used in the device.

36. A device as in claim 34 wherein, both the first and the second desired audible range of frequencies is 300 Hz to 3.3 KHz frequency range.

37. A device, comprising:

at least three microphone elements; and

at least one housing, wherein the at least one housing is configured to support the at least three microphone elements in a first orientation; and

the at least three microphones are arranged with appropriate phase and delay characteristics to achieve a substantial null response in positions having a substantially equal sound path from the at least three microphone elements over a desired audible range of frequencies; and

the device is able to provide a response to sounds over a range of second oriented elevations away from the first orientation containing the at least three microphone elements; and

the uncompensated response of the device falls off at a multiple of 6 dB per octave from high to low frequencies.

38. A device as in claim 37, wherein the at least three microphone elements are substantially equispaced in a circular arrangement with relative phases 0°

, 360°

/n, 2×

360°

/n up to (n−

1)×

360°

/n over the operating frequency range.

39. A device as in claim 37, wherein the at least three microphone elements are substantially equispaced in a first circular arrangement and the first circular arrangement has a first diameter and each microphone element has a relative phase 0°

; and

the device further comprises a second at least three microphone elements which are substantially equispaced in a second circular arrangement with a second diameter and each microphone element has a relative phase 180°

;

wherein the first diameter is greater than the second diameter.

40. A device as in claim 37 where the device is incorporated in a speakerphone.

41. A device combining a first device of claim 37 operating over part of the desired frequency range with a second device of claim 37 operating over the rest of the desired frequency range.