A System and Method for Utilizing Disjoint Audio Devices

• US 20050180582A1
• Filed: 10/14/2004
• Published: 08/18/2005
• Est. Priority Date: 02/17/2004
• Status: Abandoned Application

• Current Assignee: Isaac David Guedalia, Zvi Wolicki
• Original Assignee: Isaac David Guedalia, Zvi Wolicki
• Inventors: Guedalia, Isaac David
• Application Number:
  US10/963,512
• Publication Number:
  US 20050180582A1
• 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: H04M 3/568 audio processing specific to telephonic conferencing, e.g. spatial distribution, mixing of participants echo suppression in two-way loud-speaking telephone systems H04M9/02; sound field processing per se H04S7/30
• CPC Class Codes: H04M 7/006 Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP) , including next generation networks with a packet-switched transport layer H04L65/00 takes precedence; aspects not specific to the type of network H04M3/00; special services in those networks H04M3/42
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407

Abstract

A communication system is provided including an audio server including an audio server communicator, and a multi-aural filter, and at least one audio device including a microphone set having at least one microphone for audio acquisition of a multi-channel audio signal, and an audio device communicator for communication with the audio server via the audio server communicator, where the multi-aural filter is operative to transform the multi-channel audio signal into an audio signal suitable for communication.

Claims

1. A communication system comprising:

an audio server comprising;

an audio server communicator; and

a multi-aural filter; and

at least one audio device comprising;

a microphone set having at least one microphone for audio acquisition of a multi-channel audio signal; and

an audio device communicator for communication with said audio server via said audio server communicator,

wherein said multi-aural filter is operative to transform said multi-channel audio signal into an audio signal suitable for communication.

3. A communication system according to claim 1 wherein the pre-amplification of said microphones is configurable by said audio server.

4. A communication system according to claim 1 wherein said audio server is operative to selectably mix the output of any of said audio devices to create an audio channel for transmission to a recipient.

5. A communication system according to claim 4 wherein said audio server is operative to mix said output using an interpolative technique.

6. A communication system according to claim 1 wherein said audio server is an IP PBX.

7. A communication system according to claim 1 wherein said communication is a wireless communication.

8. A communication system according to claim 1 wherein said multi-aural filter is operative to perform Griffiths-Jim Beamforming.

9. A communication system according to claim 4 wherein said recipient is a telephone.

11. A communication system according to claim 1 wherein said microphone set further comprises a chooser and mixer operative to selectably filter output from said microphone.

12. A communication system according to claim 11 wherein said chooser and mixer is operative to determine if the output from one of said microphones is significantly better than the output of the other of said microphones utilizing a predefined measure of significance.

13. A communication system according to claim 12 wherein said chooser and mixer is operative to provide a visual indication of said microphone having said better output.

14. A communication system according to claim 11 wherein said chooser and mixer is operative to mix the output of said microphones where the output from any of said microphones is significantly better than the output of the other of said microphones.

15. A communication system according to claim 11 wherein said microphone set further comprises a pre-amp operative to amplify the signal provided by said chooser and mixer.

16. A communication system according to claim 15 wherein said microphone set further comprises an analog to digital converter operative to digitize said amplified signal.

17. A communication system according to claim 16 wherein said audio device communicator is operative to send said digitized output to said audio server.

18. A communication system according to claim 1 wherein said microphone is a unidirectional microphone having an increased sensitivity to audio signals received from a particular direction.

19. A communication system according to claim 11 wherein said microphone set comprises:

a pre-amp operative to amplify a signal provided by each of said microphones;

an analog to digital converter operative to digitize each of said amplified signals; and

a compressor operative to aggregate said digitized signals and encode said aggregated signals in a multi-channel audio format.

20. A communication system according to claim 19 wherein said audio server is operative to sensitize any of said microphones.

21. A communication system according to claim 19 wherein said audio server is operative to modify at least one encoding parameter of said compressor.

22. A communication system according to claim 19 wherein said audio server is operative to provide a feedback control to said audio device.

23. A communication system according to claim 19 wherein said feedback control is an instruction to said microphone set to illuminate an LED adjacent to the microphone whose audio channel is the clearest among said microphones.

24. A communication system according to claim 19 wherein said feedback control is an instruction to said audio device to set the volume of a speaker associated with said audio device in inverse proportion to a measure of recording clarity of said microphone sets.

25. A communication system according to claim 1 and further comprising:

a plurality of audio devices, each audio device having one of said microphone sets; and

means for inviting users of any of said audio devices to participate in a virtual telephone call.

26. A communication system according to claim 25 wherein:

said audio server is operative to emit a calibration signal from a speaker,

any of said microphones is operative to acquire said calibration signal and transmit said acquired signal to said audio server along a corresponding audio channel, and

said audio server is operative to classify said audio channels based on a standard statistical measure.

27. A communication system according to claim 26 wherein said audio server is operative to classify said audio channels whose signal exhibits a relatively high energy level as either of high energy channels and first speaker channels, and audio channels whose signal exhibits a relatively low energy level as either of low energy channels and not first speaker channels.

28. A communication system according to claim 27 wherein said audio server is operative to receive any of said audio channels acquired by said microphone sets and choose any of said audio channels not classified as first speaker channels, and wherein said microphone set further comprises a multi-aural filter operative to mix said chosen audio channels and transmit said mixed signal to a recipient.

29. A communication system according to claim 28 wherein said audio server is operative to randomly choose from among said chosen audio channels.

30. A communication system according to claim 26 wherein said audio server is operative to classify said audio channels into classes independent of said calibration.

31. A communication system according to claim 30 wherein said audio server is operative to pre-process any of said audio signals with a frequency transform, and classify said transformed signals utilizing an unsupervised clustering method.

32. A communication system according to claim 30 wherein said audio server is operative to mix each of said audio signals in any of said classes to create a single audio channel representative of said class.

33. A communication system according to claim 30 wherein said audio server is operative to choose a single one of said audio channels in any of said classes to best represent said class'"'"'s audio signal.

34. A communication system according to claim 1 wherein

a set of at least two of said microphones are distributed along the circumference of the bounding circle of said microphone set,

said audio device includes a speaker and is operative to emit a sound via said speaker, and

said audio server is operative to calculate the distance between each of said microphones based on the phase differences between the arrival of said sound at each of said microphones.

35. A communication system according to claim 1 wherein said audio server is operative to

determine the most active microphone of each set of microphone sets,

calculate the angle between said microphones based on their radial displacement within said microphone set, and

calculate the distance from a participant to said most active microphone.

36. A communication system according to claim 1 wherein said audio server is operative to

a) determine the most active microphone of each set of microphone sets,

b) determine an opposing one of said microphones;

c) calculate, respectively, the Discrete Fourier Transforms ‘

F_a’ and

‘

F_o’

in a sliding window of both said most active and opposing microphones;

d) create a mask ‘

M’

of ‘

F_o’

;

e) multiply each F_ai by ‘

M_i’

where F_ai=F_ai*M_i for all i, where, M_i, represents the mask at index i, and F_oi, represents the Discrete Fourier Transform at index I;

f) perform steps b)-e) for any other opposing ones of said microphones;

g) perform an Inverse Fourier Transform on F_a and add a portion of the original signal; and

h) normalize the audio signal of step g) to insure that the maximum values of the audio signal conform to a predefined limit.

37. A communication system according to claim 36 wherein said mask ‘

M’

is expressed as;

M_i=1−

(1.0/(1.0+exp (−

1.0*CONSTANT*F_oi)))

where, M_i, represents said mask at an index i, F_oi represents the Discrete Fourier Transform at index i, and CONSTANT is a predefined value.

38. A communication system according to claim 1 wherein said audio device further comprises:

a divider; and

at least one speaker separated from said microphone set by said divider, wherein said divider is arranged to at least partially inhibit the direct flow of sound produced by said speakers to said microphone set.

39. A communication system according to claim 38 wherein said divider has a textured surface facing said microphone set.

40. A communication system according to claim 39 wherein said textured surface is textured like the pinnea of a human ear.

41. A communication system according to claim 38 wherein said audio device further comprises:

a calibrator selectably operative to cause said speaker to emit a calibration sound, wherein said microphone set is operative to record said calibration sound; and

a multi-aural filter operative to calibrate itself using said calibration sound and determine at least one spatial feature of the environment in which said Audio Devices are deployed.

42. A communication system according to claim 1 wherein said audio device further comprises a clock operative to provide the current time to said audio device, wherein data transmitted by said audio device includes a time stamp indicating the time at which said audio signal was acquired at said audio device by said microphone set.

43. A communication system according to claim 42 and further comprising a central clock, wherein any of said audio devices are operative to synchronize its clock with said central clock.