Directional microphone utilizing spaced apart omni-directional microphones

• US 6,535,610 B1
• Filed: 02/07/1996
• Issued: 03/18/2003
• Est. Priority Date: 02/07/1996
• Status: Expired due to Fees

• Current Assignee: Legerity Incorporated (Microsemi Semiconductor Corp.)
• Original Assignee: Morgan Stanley & Co Incorporated (Morgan Stanley)
• Inventors: Stewart, Brett B.
• Primary Examiner(s): Isen, Forester W.
• Assistant Examiner(s): Grier, Laura A.
• Application Number:
  US08/598,098
• Time in Patent Office: 2,596 Days
• Field of Search: 381/97, 381/182, 381/169, 381/92
• US Class Current: 381/92
• CPC Class Codes: G06F 1/1605 Multimedia displays, e.g. with integrated or attached speakers, cameras, microphones
• CPC Class Codes: G06F 1/1616 with folding flat displays, e.g. laptop computers or notebooks having a clamshell configuration, with body parts pivoting to an open position around an axis parallel to the plane they define in closed position
• CPC Class Codes: G06F 1/1684 Constructional details or arrangements related to integrated I/O peripherals not covered by groups G06F1/1635 - G06F1/1675
• CPC Class Codes: G06F 3/16 Sound input; Sound output speech processing G10L
• CPC Class Codes: H04R 1/403 loud-speakers
• CPC Class Codes: H04R 1/406 microphones
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04R 3/12 for distributing signals to two or more loudspeakers specially adapted for hearing aids H04R25/407

Abstract

A sound processing apparatus includes a plurality of microphones spaced apart from each other, each microphone producing electrical signals representative of sound signals incident thereon. The sound processing apparatus also includes a signal processing unit that produces a specific direction sound signal by processing the electrical signals according to a specific sound direction. The plurality of microphones can be positioned about a periphery of a computer display, and adaptive beam forming techniques can be employed to provide a directional input sound signal for use in sound processing.

Claims

1. A sound processing apparatus comprising:

a computer;

a display operatively coupled to the computer;

a sound processing unit operatively controlled by the computer;

a plurality of microphones positioned about a periphery of the display, each microphone receiving a sound signal and producing an analog signal representative of said sound signal;

an analog to digital converter circuit sampling the analog signal from each microphone at variable sampling intervals determined by the computer and producing a digital signal corresponding to each sampled analog signal;

a selector providing a specific sound direction signal; and

a signal processing unit receiving the specific sound direction signal and said digital signals and processing said digital signals according to the specific sound direction signal to produce, as input to the sound processing unit, a directional input sound signal.

2. The sound processing apparatus of claim 1, wherein the selector utilizes adaptive beam forming techniques to provide the directional input sound signal.

3. A sound processing system comprising:

a computer;

a sound processing unit controlled by the computer;

a display connected to the computer;

a first microphone positioned at the top left corner of the display and connected to a first analog to digital converter to produce a first microphone signal;

a second microphone positioned at the top right corner of the display and connected to a second analog to digital converter to produce a second microphone signal;

a third microphone positioned at the bottom right corner of the display and connected to a third analog to digital converter to produce a third microphone signal;

a fourth microphone positioned at the bottom left corner of the display and connected to a fourth analog to digital converter to produce a fourth microphone signal;

a first tapped delay line connected to the first microphone signal, wherein said first tapped delay line comprises a plurality of taps at adjustable relative time delays, each tap multiplied by an adjustable weight factor, and each tap added to a subsequent weight adjusted tap to produce a first microphone output signal;

a second tapped delay line connected to the second microphone signal, wherein said second tapped delay line comprises a plurality of taps at adjustable relative time delays, each tap multiplied by an adjustable weight factor, and each tap added to a subsequent weight adjusted tap to produce a second microphone output signal;

a third tapped delay line connected to the third microphone signal, wherein said third tapped delay line comprises a plurality of taps at adjustable relative time delays, each tap multiplied by an adjustable weight factor, and each tap added to a subsequent weight adjusted tap to produce a third microphone output signal;

a fourth tapped delay line connected to the fourth microphone signal, wherein said fourth tapped delay line comprises a plurality of taps at adjustable relative time delays, each tap multiplied by an adjustable weight factor, and each tap added to a subsequent weight adjusted tap to produce a fourth microphone output signal;

a direction setting element responsive to an external signal to set said adjustable relative time delays and said adjustable weight factors to form and steer a beam having a selectively adjustable width in a direction specified by the external signal; and

an output of the signal processing unit comprising the sum of the first, second, third, and fourth microphone output signals connected to the sound processing unit.