Acoustic perimeter for reducing noise transmitted by a communication device in an open-plan environment
The amount of far-field noise transmitted by a primary communication device in an open-plan office environment is reduced by defining an acoustic perimeter of reference microphones around the primary device. Reference microphones generate a reference audio input including far-field noise in the proximity of the primary device. The primary device generates a main audio input including the voice of the primary speaker as well as background noise. Reference audio input is compared to main audio input to identify the background noise portion of the main audio signal. A noise reduction algorithm suppresses the identified background noise in the main audio signal. The one or more reference microphones defining the acoustic perimeter may be included in separate microphone devices placed in proximity to the main desktop phone, microphones within other nearby desktop telephone devices, or a combination of both types of devices.
1. A primary communication device for use in an environment, the environment including:
a first primary communication device configured to transmit a first speaker's voice from the first primary communication device to a first receiving communication device, wherein the first primary communication device includes a first main microphone;
a second primary communication device configured to transmit a second speaker's voice from the second primary communication device to a second receiving communication device, wherein the second primary communication device includes a second main microphone;
a plurality of reference microphones, with each reference microphone in a different device, a first subset of the plurality of reference microphones forming a first perimeter about the first primary communication device and a second subset of the plurality of reference microphones forming a second perimeter about the second primary communication device;
a first processor configured to:
receive a first main audio input from the first main microphone;
receive first subset reference audio inputs from each of the reference microphones in the first subset, wherein the first subset reference audio inputs include far field noise with respect to the first primary communication device;
generate a first reduced-noise audio output having suppressed far field noise based on a comparison of at least one of the first subset reference audio inputs and the first main audio input; and
provide the first reduced-noise audio output for transmission to the first receiving communication device; and
a second processor configured to:
receive a second main audio input from the second main microphone;
receive second subset reference audio inputs from each of the reference microphones in the second subset, wherein the second subset reference audio inputs include far field noise with respect to the second primary communication device;
generate a second reduced-noise audio output having suppressed far field noise based on a comparison of at least one of the second subset reference audio inputs and the second main audio input; and
provide the second reduced-noise audio output for transmission to the first receiving communication device,
the primary communication device comprising:
a microphone; and
a processor coupled to the microphone,
wherein the primary communication device acts as both the first primary communication device and one of the second subset of the plurality of reference microphones,
wherein the microphone of the primary communication device acts as the first main microphone of the first primary communication device and acts as one of the second subset of the plurality of reference microphones, and
wherein the processor of the primary communication device acts as the first processor and is further configured to provide an audio output of the microphone as a reference audio input to the second processor.
2. The primary communication device of claim 1 , wherein the primary communication device acts as the first primary communication device at one time and acts as the one of the second subset of the plurality of reference microphones at another time.
3. The primary communication device of claim 1 , wherein the primary communication device acts as the first primary communication device and acts as the one of the second subset of the plurality of reference microphones at the same time.
4. The primary communication device of claim 1 , wherein the processor is further configured to mute the main microphone when the comparison of the reference audio inputs to the main audio input indicates that the main audio input does not include a speaker's voice.
5. The primary communication device of claim 1 , wherein the processor is further configured to subtract an estimate of the far-field noise from the main audio signal, wherein the estimate of the far-field noise is determined based on the comparison of the main audio input to at least one reference audio input.
6. The primary communication device of claim 1 , wherein the processor is further configured to subtract an estimate of the far-field noise from the main audio signal, wherein the estimate of the far-field noise is determined based on the comparison of the main audio input to at least one reference audio input received from reference microphones within the acoustic perimeter.
7. The primary communication device of claim 1 , wherein the processor is further configured to select, from the plurality of reference audio inputs, the reference audio input having the highest energy for comparison to the main audio input.
8. The primary communication device of claim 1 , wherein the primary communication device is a speakerphone, and
wherein the plurality of reference microphones are some combination of speakerphones, overhead microphones and cubicle wall microphones.
9. A method for audio processing in an environment, the environment including:
a first primary communication device configured to transmit a first speaker's voice from the first primary communication device to a first receiving communication device, wherein the first primary communication device includes a first main microphone;
a second primary communication device configured to transmit a second speaker's voice from the second primary communication device to a second receiving communication device, wherein the second primary communication device includes a second main microphone;
a plurality of reference microphones, with each reference microphone in a different device, a first subset of the plurality of reference microphones forming a first perimeter about the first primary communication device and a second subset of the plurality of reference microphones forming a second perimeter about the second primary communication device;
a first processor configured to:
receive a first main audio input from the first main microphone;
receive first subset reference audio inputs from each of the reference microphones in the first subset, wherein the first subset reference audio inputs include far field noise with respect to the first primary communication device;
generate a first reduced-noise audio output having suppressed far field noise based on a comparison of at least one of the first subset reference audio inputs and the first main audio input; and
provide the first reduced-noise audio output for transmission to the first receiving communication device; and
a second processor configured to:
receive a second main audio input from the second main microphone;
receive second subset reference audio inputs from each of the reference microphones in the second subset, wherein the second subset reference audio inputs include far field noise with respect to the second primary communication device;
generate a second reduced-noise audio output having suppressed far field noise based on a comparison of at least one of the second subset reference audio inputs and the second main audio input; and
provide the second reduced-noise audio output for transmission to the first receiving communication device,
the method comprising:
operating a primary communication device having a microphone and a processor coupled to the microphone to act as both the first primary communication device and one of the second subset of the plurality of reference microphones,
wherein the microphone of the primary communication device acts as the first main microphone of the first primary communication device and acts as one of the second subset of the plurality of reference microphones, and
wherein the processor of the primary communication device acts as the first processor and is further configured to provide an audio output of the microphone as a reference audio input to the second processor.
10. The method of claim 9 , wherein the primary communication device acts as the first primary communication device at one time and acts as the one of the second subset of the plurality of reference microphones at another time.
11. The method of claim 9 , wherein the primary communication device acts as the first primary communication device and acts as the one of the second subset of the plurality of reference microphones at the same time.
12. The method of claim 9 , wherein generating a reduced-noise audio output comprises:
muting the main microphone when the comparison of the reference audio inputs to the main audio input indicates that the main audio input does not include a speaker's voice.
13. The method of claim 9 , wherein generating a reduced-noise audio output comprises:
subtracting an estimate of the far-field noise from the main audio signal, wherein the estimate of the far-field noise is determined based on the comparison of the main audio input to at least one reference audio input.
14. The method of claim 9 , further comprising:
selecting, from the plurality of reference audio inputs, the reference audio input having the highest energy for comparison to the main audio input.
15. A non-transitory storage medium storing programs for execution by a processor that cause the processor to perform the following method when executed on the processor, the processor included in a primary communication device for use in an environment, the environment including:
a first primary communication device configured to transmit a first speaker's voice from the first primary communication device to a first receiving communication device, wherein the first primary communication device includes a first main microphone;
a second primary communication device configured to transmit a second speaker's voice from the second primary communication device to a second receiving communication device, wherein the second primary communication device includes a second main microphone;
a plurality of reference microphones, with each reference microphone in a different device, a first subset of the plurality of reference microphones forming a first perimeter about the first primary communication device and a second subset of the plurality of reference microphones forming a second perimeter about the second primary communication device;
a first processor configured to:
receive a first main audio input from the first main microphone;
receive first subset reference audio inputs from each of the reference microphones in the first subset, wherein the first subset reference audio inputs include far field noise with respect to the first primary communication device;
generate a first reduced-noise audio output having suppressed far field noise based on a comparison of at least one of the first subset reference audio inputs and the first main audio input; and
provide the first reduced-noise audio output for transmission to the first receiving communication device; and
a second processor configured to:
receive a second main audio input from the second main microphone;
receive second subset reference audio inputs from each of the reference microphones in the second subset, wherein the second subset reference audio inputs include far field noise with respect to the second primary communication device;
generate a second reduced-noise audio output having suppressed far field noise based on a comparison of at least one of the second subset reference audio inputs and the second main audio input; and
provide the second reduced-noise audio output for transmission to the first receiving communication device,
the method comprising:
operating a primary communication device having a microphone, a processor coupled to the microphone and a non-transitory storage medium storing programs coupled to the processor to act as both the first primary communication device and one of the second subset of the plurality of reference microphones,
wherein the microphone of the primary communication device acts as the first main microphone of the first primary communication device and acts as one of the second subset of the plurality of reference microphones, and
wherein the processor of the primary communication device acts as the first processor and is further configured to provide an audio output of the microphone as a reference audio input to the second processor.
16. The non-transitory storage medium of claim 15 , wherein the primary communication device acts as the first primary communication device at one time and acts as the one of the second subset of the plurality of reference microphones at another time.
17. The non-transitory storage medium of claim 15 , wherein the primary communication device acts as the first primary communication device and acts as the one of the second subset of the plurality of reference microphones at the same time.
18. The non-transitory storage medium of claim 15 , wherein generating a reduced-noise audio output comprises:
muting the main microphone when the comparison of the reference audio inputs to the main audio input indicates that the main audio input does not include a speaker's voice.
19. The non-transitory storage medium of claim 15 , wherein generating a reduced-noise audio output comprises:
subtracting an estimate of the far-field noise from the main audio signal, wherein the estimate of the far-field noise is determined based on the comparison of the main audio input to at least one reference audio input.
20. The non-transitory storage medium of claim 15 , further comprising:
selecting, from the plurality of reference audio inputs, the reference audio input having the highest energy for comparison to the main audio input.