Apparatus and method for noise cancellation in communication headset using dual-coil speaker

• US 20070041606A1
• Filed: 08/22/2005
• Published: 02/22/2007
• Est. Priority Date: 08/22/2005
• Status: Abandoned Application

• Current Assignee: David Clark Company Incorporated
• Original Assignee: David Clark Company Incorporated
• Inventors: Sheppard, Allan
• Application Number:
  US11/208,975
• Publication Number:
  US 20070041606A1
• Time in Patent Office: Days
• US Class Current: 381/401
• CPC Class Codes: H04R 1/1008 Earpieces of the supra-aural or circum-aural type
• CPC Class Codes: H04R 1/1083 Reduction of ambient noise active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06
• CPC Class Codes: H04R 5/033 Headphones for stereophonic communication details thereof, e.g. relating to batteries, cables or control elements H04R1/10

Abstract

A communication headset is disclosed that includes a speaker assembly. The speaker assembly includes at least a first speaker coil and a second speaker coil. One speaker coil is for receiving a communication signal, and another speaker coil is for receiving an active noise cancellation signal. Each of the speaker coils co-acts with a magnetic field for causing a diaphragm to move responsive to the communication signal and the active noise cancellation signal individually or simultaneously.

Claims

1. A device for canceling noise, comprising:

a first speaker coil for receiving a communication signal;

a second speaker coil for receiving an active noise cancellation signal, each of the first and second speaker coils co-acting with a magnetic field for causing a diaphragm to move responsive to each of the communication signal and the active noise cancellation signal.

2. The device as claimed in claim 1, wherein the first and second speaker coils are concentric.

3. The device as claimed in claim 1, wherein the first and second speaker coils are helical.

4. The device as claimed in claim 1, wherein the first and second speaker coils are layered.

5. The device as claimed in claim 1, wherein the device for canceling noise further includes a microphone that provides a background signal to a feedback network, and the active noise cancellation signal is produced responsive to the background signal.

6. The device as claimed in claim 5, wherein the feedback network includes a communication equalizer for preconditioning an input signal.

7. The device as claimed in claim 1, further comprising a digital signal processor.

8. The device as claimed in claim 7, wherein the digital signal processor includes at least one of a digitally created analog output signal, a pulse width modulated output signal, and a pulse width and frequency modulated output signal.

9. The device as claimed in claim 1, wherein the device for canceling noise further includes a low impedance passive network for equalizing the communication signal before the communication signal is applied to the first speaker coil.

10. The device as claimed in claim 1, wherein the magnetic field extends radially outwardly from a magnet through the first and second speaker coils and returns to the magnet via a magnetic structure.

11. The device as claimed in claim 10, wherein the magnet structure includes the magnet, a cup shaped structure, and a plate, the magnet being positioned between the cup shaped structure and the plate.

12. The device as claimed in claim 10, wherein the first and second speaker coils are positioned to pass through an annular opening in the magnetic structure.

13. A speaker for noise cancellation, comprising:

a first speaker coil for receiving a communication signal, the first speaker coil being coupled to a diaphragm;

a second speaker coil for receiving an active noise cancellation signal, the second speaker coil being coupled to the diaphragm;

a magnet being positioned such that a magnetic field extends through the first and second speaker coils.

14. The speaker as claimed in claim 13, wherein the first and second speaker coils are concentric.

15. The speaker as claimed in claim 13, wherein the first and second speaker coils are helical.

16. The speaker as claimed in claim 13, wherein the first and second speaker coils are layered.

17. The speaker as claimed in claim 13, wherein the speaker is coupled to a microphone that provides a background signal to a feedback network, and the active noise cancellation signal is produced responsive to the background signal.

18. The speaker as claimed in claim 17, wherein the feedback network includes a loop equalizer for filtering and amplifying the background signal.

19. The speaker as claimed in claim 17, wherein the feedback network includes a communication equalizer for preconditioning an input signal.

20. The speaker as claimed in claim 17, wherein the feedback network includes a digital signal processor.

21. The speaker as claimed in claim 20, wherein the digital signal processor includes at least one of a digitally created analog output signal, a pulse width modulated output signal, and a pulse width and frequency modulated output signal.

22. The speaker as claimed in claim 13, wherein the speaker is coupled to a low impedance passive network for equalizing the communication signal before the communication signal is applied to the first speaker coil.

23. The speaker as claimed in claim 13, wherein the magnetic field extends radially outward from the magnet through the first and second speaker coils and returns to the magnet via a magnetic structure.

24. The speaker as claimed in claim 23, wherein the magnet structure includes the magnet, a cup shaped structure, and a plate, the magnet being positioned between the cup shaped structure and the plate.

25. The speaker as claimed in claim 23, wherein the first and second speaker coils are positioned to pass through an annular opening in the magnetic structure.

26. The speaker as claimed in claim 13, wherein the diaphragm is coupled to an outer shell and includes folds in the diaphragm to facilitate protrusion and retraction of the diaphragm with respect to the outer shell.

27. The speaker as claimed in claim 13, wherein the diaphragm comprises a center diaphragm and an annular diaphragm.

28. The speaker as claimed in claim 13, wherein the diaphragm comprises a single unitary diaphragm.

29. The speaker as claimed in claim 13, wherein first and second speaker coils acting with the magnetic field cause the diaphragm to move responsive to each of the communication signal and the active noise cancellation signal.

30. The speaker as claimed in claim 13, wherein the speaker is coupled to a microphone that provides a background signal to a feedforward network, and the active noise cancellation signal is produced responsive to the background signal.

31. The speaker as claimed in claim 13, wherein the speaker is a headset speaker.

32. A communication headset including a speaker assembly, said speaker assembly comprising:

a first speaker coil for receiving a communication signal; and

a second speaker coil for receiving an active noise cancellation signal, each of the first and second speaker coils co-acting with a magnetic field for causing a diaphragm to move responsive to each of the communication signal and the active noise cancellation signal.

33. The communication headset as claimed in claim 32, wherein the first and second speaker coils are concentric.

34. The communication headset as claimed in claim 32, wherein the first and second speaker coils are helical.

35. The communication headset as claimed in claim 32, wherein the first and second speaker coils are layered.

36. The communication headset as claimed in claim 32, wherein the speaker assembly is coupled to a microphone that provides a background signal to a feedback network, and the active noise cancellation signal is produced responsive to the background signal.

37. The communication headset as claimed in claim 36, wherein the feedback network includes a communication equalizer for preconditioning an input signal.

38. The communication headset as claimed in claim 36, wherein the feedback network includes a digital signal processor.

39. The communication headset as claimed in claim 38, wherein the digital signal processor includes at least one of a digitally created analog output signal, a pulse width modulated output signal, and a pulse width and frequency modulated output signal.

40. The communication headset as claimed in claim 32, wherein the speaker assembly is coupled to a low impedance passive network for equalizing the communication signal before the communication signal is applied to the first speaker coil.

41. The communication headset as claimed in claim 32, wherein the magnetic field extends radially outwardly from a magnet through the first and second speaker coils and returns to the magnet via a magnetic structure.

42. The communication headset as claimed in claim 41, wherein the magnet structure includes a magnet, a cup shaped structure, and a plate, the magnet being positioned between the cup shaped structure and the plate.

43. The communication headset as claimed in claim 41, wherein the first and second speaker coils are positioned to pass through an annular opening in the magnetic structure.