Virtual microphones in electronic conferencing systems

• US 20050271220A1
• Filed: 06/02/2004
• Published: 12/08/2005
• Est. Priority Date: 06/02/2004
• Status: Active Grant

• Current Assignee: Clearone Incorporated
• Original Assignee: Clearone Incorporated
• Inventors: Bathurst, Tracy A., Lambert, David
• Granted Patent: US 8,644,525 B2
• Time in Patent Office: Days
• US Class Current: 381/92
• CPC Class Codes: H04M 3/56 Arrangements for connecting several subscribers to a common circuit, i.e. affording conference facilities video conference systems H04N7/15
• CPC Class Codes: H04R 1/406 microphones

Abstract

Disclosed herein are electronic conferencing systems that support audio conversations between local and remote participants. Further disclosed herein are methods for combining several microphones to form virtual microphones and conference pods that utilize those methods. Detailed information on various example embodiments of the inventions are provided in the Detailed Description below, and the inventions are defined by the appended claims.

Claims

1. A pod intended for use in a conference system, said pod comprising:

a loudspeaker;

a plurality of microphones;

a processor;

samplers for receiving an incoming audio signal and for receiving input from said microphones by said processor;

at least one loudspeaker driver for driving audio from said loudspeaker such that the driven audio may be heard at an appreciable distance from said loudspeaker;

a driver for injecting an audio signal into an outgoing audio stream carrier;

wherein said pod combines the input of two microphone inputs by adding the signal of one input to the inverse of the other input, the combination yielding a virtual microphone signal; and

providing at least a portion of said virtual microphone signal to said driver.

2. A pod according to claim 1, wherein the combining of the input of microphone inputs is performed by said processor.

3. A pod according to claim 2, wherein said microphones are bi-polar microphones.

4. A pod according to claim 3, wherein said bi-polar microphones are positioned within said pod such that sound originating said loudspeaker travels along a path that is substantially the same length to both poles of each of said microphones.

5. A pod according to claim 4, further comprising a pair of ports for each of said microphones, and for each pair of ports, wherein said pod provides a path from one port to a pole of a microphone, further wherein said pod provides a different path from the other port to the opposite pole of the microphone, and further wherein the two paths are substantially isolated between the respective ports and microphone poles such that sound does not mix between the two paths.

6. A pod according to claim 1, wherein said microphones are substantially arranged in a horizontal plane with the pod in a resting position.

7. A pod according to claim 1, wherein said processor selects one of said virtual microphones to provide output to said driver.

8. A pod according to claim 1, wherein said processor selects one microphone from the group of available physical microphones and virtual microphones.

9. A pod according to claim 8, wherein said pod provides a volume correction applied to one of the groups of available physical microphones or virtual microphones.

10. A pod according to claim 9, wherein the volume correction provides a substantially constant gain of the audio to said driver regardless of whether a physical or a virtual microphone is selected.

11. A pod according to claim 10, wherein the pod further comprises a transceiver operable to communicate data to and from another pod over a communication medium;

and further wherein;

said pod computes an internal loudness measurement;

said pod sends and receives loudness information to and from another pod by way of said transceiver; and

said pod operates to gate on and off using the internal loudness measurement and received loudness information.

12. A full-duplex electronic conferencing system, comprising:

a network of pods, said network comprising a plurality of pods, each of said pods including at least one loudspeaker and a driver for driving audio from said loudspeaker such that the driven audio may be heard at an appreciable distance from said loudspeaker, each of said pods further including a plurality of microphones and samplers for receiving input from said microphones, each of said pods further including a driver for injecting an audio signal into an outgoing audio stream carrier, said network further interconnecting said pods and providing for data transfer between pods;

a connection facility for connecting to a carrier medium;

an echo canceller, said canceller operable to reduce the sound produced by the speakers of said plurality of pods from the outgoing audio stream;

an incoming audio channel;

an outgoing audio channel;

wherein during a conference said pods are operable to contribute sound input from pod microphones to said outgoing audio channel; and

wherein said pods are operable to produce an audio signal transferred through said incoming audio channel at said loudspeakers that may be heard at an appreciable distance from said pods;

wherein each of said pods is operable to combine the input of two microphone inputs by adding the signal of one input to the inverse of the other input, the combination yielding a virtual microphone signal; and

wherein each of said pods is further operable to provide at least a portion of said virtual microphone signal to said driver of the pod.

13. A system according to claim 12, wherein the combining of the input of microphone inputs is performed by a processor contained in each of said pods.

14. A system according to claim 12, wherein said microphones are bi-polar microphones.

15. A system according to claim 14, wherein said bi-polar microphones are positioned within said pods such that sound originating said loudspeaker travels along a path that is substantially the same length to both poles of each of said microphones.

16. A system according to claim 15, wherein each of said pods further comprises a pair of ports for each of said microphones, and for each pair of ports, wherein the pod provides a path from one port to a pole of a microphone, further wherein the pod provides a different path from the other port to the opposite pole of the microphone, and further wherein the two paths are substantially isolated between the respective ports and microphone poles such that sound does not mix between the two paths.

17. A system according to claim 12, wherein while each of said pods is operating one of said virtual microphones is selected to provide output to said driver.

18. A system according to claim 12, wherein one microphone from the group of available physical microphones and virtual microphones is selected.

19. A system according to claim 18, wherein a volume correction applied to one of the groups of available physical microphones or virtual microphones.

20. A system according to claim 19, wherein the volume correction provides a substantially constant gain of the audio to said driver regardless of whether a physical or a virtual microphone is selected.

21. A system according to claim 12, wherein each of said pods is further operable to communicate keypress information to said network whereby an action associated with a keypress may be taken by the entire system.

22. A pod intended for use in a conference system, said pod comprising:

a loudspeaker;

a plurality of bi-polar microphones positioned within said pod such that sound originating said loudspeaker travels along a path that is substantially the same length to both poles of each of said microphones;

a pair of ports for each of said microphones, and for each pair of ports, wherein said pod provides a path from one port to a pole of a microphone, further wherein said pod provides a different path from the other port to the opposite pole of the microphone, and further wherein the two paths are substantially isolated between the respective ports and microphone poles such that sound does not mix between the two paths;

a processor;

samplers for receiving an incoming audio signal and for receiving input from said microphones by said processor;

at least one loudspeaker driver for driving audio from said loudspeaker such that the driven audio may be heard at an appreciable distance from said loudspeaker;

a driver for injecting an audio signal into an outgoing audio stream carrier;

wherein said pod combines the input of two microphone inputs by adding the signal of one input to the inverse of the other input, the combination yielding a virtual microphone signal;

wherein the pod may select a virtual microphone signal to output, and

providing at least a portion of a virtual microphone signal to said driver while a virtual microphone is selected.