Person monitoring

• US 7,525,440 B2
• Filed: 06/01/2005
• Issued: 04/28/2009
• Est. Priority Date: 06/01/2005
• Status: Active Grant

• Current Assignee: Bose Corporation
• Original Assignee: Bose Corporation
• Inventors: Hertzberg, Marc, Gomes-Casseres, Glenn, Najemy, Daniel D., Wakeland, Ray, Carreras, Ricardo F.
• Primary Examiner(s): Pham; Toan N
• Assistant Examiner(s): Mehmood; Jennifer
• Application Number:
  US11/142,749
• Publication Number:
  US 20060273914A1
• Time in Patent Office: 1,427 Days
• Field of Search: 340/500, 340/501, 340/573.1, 340/692, 381/26, 381/56, 381/57, 381 99-103, 181/18, 181/19, 181/139
• US Class Current: 340/573.1
• CPC Class Codes: G10L 21/0208 Noise filtering

Abstract

A person monitoring system, such as a baby monitor a monitored unit including a microphone for transducing radiated sound waves and sound waves emanating from the person to a received audio signal and circuitry for removing from the received audio signal a portion of the received audio signal corresponding to the radiated sound waves to provide an audio signal corresponding to the sound waves emanating from the person.

Claims

1. A person monitoring system comprising:

a monitored unit comprising a microphone for transducing radiated sound waves and sound waves emanating from the person to a received audio signal and circuitry for removing from the received audio signal a portion of the received audio signal corresponding to the radiated sound waves to provide a first processed received audio signal corresponding to the sound waves emanating from the person, the monitored unit further comprising;

an audio signal source for providing a source audio signal; and

a loudspeaker for transducing the source audio signal to provide the radiated sound waves.

2. A person monitoring system in accordance with claim 1, the monitored unit further comprising:

a unitary housing for the audio signal source, the microphone, and the circuitry.

3. A person monitoring system in accordance with claim 1, wherein the monitored unit comprises transmitting circuitry to wirelessly broadcast the first processed received audio signal to provide a broadcast processed received audio signal, the monitoring system further comprising a monitoring unit, the monitoring unit comprising

receiving circuitry for receiving the broadcast processed received audio signal;

and

a transducer for transducing the broadcast processed received audio signal to sound waves.

4. A person monitoring system in accordance with claim 2, wherein the microphone is constructed and arranged to remotely transduce the radiated sound waves and the sound waves emanating from the person to provide the received audio signal and further constructed and arranged to transmit the received audio signal to the removing circuitry.

5. A person monitoring system in accordance with claim 4, wherein the microphone is constructed and arranged to transmit wirelessly the received audio signal.

6. A person monitoring system in accordance with claim 1, the monitored unit further comprising a first housing for the microphone and the removing circuitry and a second housing, separate from the first housing for the audio signal source and the loudspeaker.

7. A person monitoring system in accordance with claim 1, the monitored unit further comprising:

transmitting circuitry for transmitting the first processed received audio signal to a monitoring device.

8. A person monitoring system in accordance with claim 7, wherein the monitoring device is a network for providing the first processed received audio signal to devices accessible by the network.

9. A person monitoring system in accordance with claim 1, the monitored unit further comprising:

transmitting circuitry to transmit the first processed received audio signal.

10. A person monitoring system in accordance with claim 9, further comprising:

a first monitoring unit, comprising receiving circuitry for receiving the transmitted first processed received audio signal from the monitored unit.

11. A person monitoring system in accordance with claim 10 further comprising a second monitoring unit comprising receiving circuitry for receiving the first transmitted processed received audio signal from the monitored unit.

12. A person monitoring system in accordance with claim 9, wherein the transmitting circuitry comprises circuitry to wirelessly broadcast the first processed received audio signal to provide a broadcast processed received audio signal.

13. A person monitoring system in accordance with claim 12, further comprising:

a monitoring unit, the monitoring unit comprising

receiving circuitry for wirelessly receiving the broadcast processed received audio signal.

14. A person monitoring system in accordance with claim 13, the monitoring unit further comprising a transducer for transducing the broadcast processed received audio signal to sound waves.

15. A person monitoring system in accordance with claim 9, further comprising a monitoring unit comprising circuitry for receiving the first transmitted processed received audio signal and for providing the first processed received audio signal to an audio signal network, to transmit the first processed received audio signal to devices coupled to the audio signal network.

16. A person monitoring system in accordance with claim 9, further comprising a second monitored unit comprising:

a second microphone for transducing second radiated sound waves and second sound waves emanating from a second person to a second received audio signal;

second circuitry for removing from the second received audio signal a portion of the second received audio signal corresponding to the second radiated sound waves to provide a second processed received audio signal corresponding to the second sound waves emanating from the second person; and

second transmitting circuitry to transmit the second processed received audio signal.

41. A person monitoring system in accordance with claim 1, wherein the circuitry for removing from the received audio signal a portion of the received audio signal corresponding to the radiated sound waves to provide a first processed received audio signal corresponding to the sound waves emanating from the person comprises an adaptive filter.

42. A person monitoring system in accordance with claim 1, wherein the circuitry for removing from the received audio signal a portion of the received audio signal corresponding to the radiated sound waves to provide a first processed received audio signal corresponding to the sound waves emanating from the person further comprises a non-linear filter, operationally coupled to the adaptive filter.

43. A person monitoring system in accordance with claim 1, wherein the circuitry for removing from the received audio signal a portion of the received audio signal corresponding to the radiated sound waves to provide a first processed received audio signal corresponding to the sound waves emanating from the person further comprises a second adaptive filter.

44. A person monitoring system in accordance with claim 42, wherein the second adaptive filter is a predictive adaptive filter.

17. A person monitoring system comprising:

a monitored unit comprising a first microphone for transducing radiated sound waves and sound waves emanating from the person to a received audio signal and circuitry for removing from the received audio signal a portion of the received audio signal corresponding to the radiated sound waves to provide a first processed received audio signal corresponding to the sound waves emanating from the person,

the monitored unit further comprising transmitting circuitry to transmit the first processed received audio signal,

the person monitoring system further comprising a second monitored unit comprising

a second microphone for transducing second radiated sound waves and second sound waves emanating from a second person to a second received audio signal;

second circuitry for removing from the second received audio signal a portion of the second received audio signal corresponding to the second radiated sound waves to provide a second processed received audio signal corresponding to the second sound waves emanating from the second person; and

second transmitting circuitry to transmit the second processed received audio signal, the person monitoring system further comprising

a monitoring unit, the monitoring unit comprising

receiving circuitry for receiving the first broadcast processed received audio signal and the second broadcast processed received audio signal; and

circuitry for determining which of the first processed received audio signal and the second processed received audio signal to monitor.

18. A person monitoring system in accordance with claim 17, further comprising:

a second monitoring unit, the second monitoring unit comprising

second receiving circuitry for receiving broadcast processed received audio signals; and

second circuitry for determining which of the first processed received audio signal and the second processed received audio signal to monitor.

19. A person monitoring system comprising:

a monitored unit comprising a microphone for transducing radiated sound waves and sound waves emanating from the person to a received audio signal and circuitry for removing from the received audio signal a portion of the received audio signal corresponding to the radiated sound waves to provide a first processed received audio signal corresponding to the sound waves emanating from the person,

the monitored unit further comprising transmitting circuitry to transmit the first processed received audio signal,

the person monitoring system further comprising

a first monitoring unit, comprising receiving circuitry for receiving the transmitted first processed received audio signal from the monitored unit; and

determining circuitry to determine which of the first processed received audio signal and the second processed received audio signal to monitor,

wherein the determining circuitry comprises

circuitry for comparing the amplitude of the first processed received audio signal and the amplitude of the second processed received audio signal; and

circuitry for selecting one of the first processed received audio signal and the second processed received audio signal corresponding to the processed received audio signal with the greater amplitude.

20. A method for operating a person monitoring system, comprising:

providing a source audio signal;

transducing the source audio signal to radiated sound waves, the transducing including radiating sound waves from a loudspeaker;

transducing sound waves including the radiated sound waves and sound waves emanating from a person to a received audio signal, the transducing including receiving the sound waves by a microphone; and

removing a portion of the received audio signal corresponding to the radiated sound waves to provide a processed audio signal corresponding substantially to the sound waves emanating from the person.

21. A method in accordance with claim 20, wherein

the transducing sound waves includes transducing sound waves from a noise source, and further comprising:

removing a portion of the received audio signal corresponding to the sound waves from the noise source.

22. A method in accordance with claim 21, wherein the removing a portion of the received audio signal corresponding to the sound waves from the noise source comprises filtering the received audio signal with an adaptive filter.

23. A method in accordance with claim 22, wherein filtering the received audio signal with an adaptive filter comprises:

transducing, separate from the transducing sound radiated sound waves, sound waves emanating from the person and sound waves from the noise source, by a microphone substantially closer to the noise source than to other sources of sound waves to provide transduced sound waves, and

providing the transduced sound waves to the adaptive filter.

24. A method in accordance with claim 20, wherein the removing comprises band pass filtering the received audio signal.

25. A method in accordance with claim 24, wherein the band pass filtering comprises filtering the received audio signal with a filter with a pass band substantially corresponding with the speech audio band.

26. A method in accordance with claim 25, wherein the band pass filtering comprises filtering the received audio signal with a filter with break points of approximately 300 Hz and 3 kHz.

27. A method in accordance with claim 20, wherein the removing comprises filtering the received audio signal with an adaptive filter.

28. A method in accordance with claim 27, further comprising providing the source audio signal to the adaptive filter.

29. A method in accordance with claim 20, wherein the transducing the source audio signal comprises directionally radiating the sound waves so that a direction toward the microphone is a low radiation direction.

30. A method in accordance with claim 29, wherein the transducing the sound waves comprises directionally receiving the sound waves so that a direction from the loudspeaker is a low response direction.

31. A method in accordance with claim 30, wherein the directionally receiving the sound waves comprises:

a first receiving by a first substantially omni-directional microphone to provide a first omni-directionally received audio signal;

a second receiving by a second substantially omni-directional microphone to provide a second omni-directionally received audio signal;

adjusting the phase of the first omni-directionally received audio signal and the second omni-directionally received audio signal to provide phase-adjusted first and second received omni-directionally received audio signals; and

combining the first and the second omni-directionally received audio signals.

32. A method in accordance with claim 29, wherein the directionally radiating the sound waves comprises:

low pass filtering the source audio signal to provide a low pass filtered audio signal;

high pass filtering the source audio signal to provide a high pass filtered audio signal;

a first combining of the high pass filtered audio signal and the low pass filtered audio signal to provide a first combined audio signal having a high frequency spectral band and a low frequency spectral band;

a differential second combining of the high pass filtered audio signal and the low pass audio signal to provide a second combined audio signal having a high frequency spectral band and a low frequency spectral band;

radiating the first combined audio signal and the second combined audio signal so that sound waves corresponding to the high frequency spectral band of the first combined audio signal high are radiated out of phase with the high frequency spectral band portion of the second combined audio signal.

33. A method in accordance with claim 29, wherein the source audio signal has a high frequency portion and a low frequency portion, the providing the source audio signal comprising:

providing a first track and a second track of the source audio signal wherein the first track and the second track each comprise a high frequency portion and a low frequency portion, wherein the providing the first track and the second track comprises processing the source audio signal high frequency portion so that high frequency portion of the first track high is out of phase with the high frequency portion of the second track.

34. A method in accordance with claim 20, further comprising transmitting the processed audio signal to a location remote from the person to provide a received processed audio signal.

35. A method in accordance with claim 34, further comprising transducing the received processed audio signal to sound waves corresponding to the received processed audio signal.

36. A method in accordance with claim 34, further comprising, in the absence of sound waves emanating from the person, transmitting an audio signal representing white noise.

37. A method in accordance with claim 20, wherein the receiving the sound waves by a microphone comprises receiving the sound waves by a microphone that is physically close to the person and wherein the microphone is physically distant from circuitry for performing the removing.

38. A method in accordance with claim 20, further comprising transmitting the processed audio signal to an audio network.

39. A method in accordance with claim 20, wherein the removing comprises:

radiating sound waves corresponding to an audio signal representing an audio test pattern;

transducing the sound waves corresponding to the audio signal representing the audio test pattern to a received audio test pattern audio signal; and

comparing the received audio test pattern audio signal with the audio signal representing the audio test pattern to develop a transfer function representing the effect of the environment on the radiated sound waves corresponding to the audio signal representing the audio test pattern to a received audio test pattern audio signal.

40. A person monitoring system, comprising:

a first monitored unit for transducing to a first audio signal sound waves emanating from a first person and for transmitting the first audio signal;

a second monitored unit for transducing to a second audio signal sound waves emanating from a second person and for transmitting the second audio signal;

a monitoring unit for receiving the first audio signal and the second audio signal, the monitoring unit comprising circuitry for comparing the amplitude of the first audio signal and the amplitude of the second audio signal; and

circuitry for selecting one of the first audio signal and the second audio signal corresponding to the audio signal with the greater amplitude.