The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 17, 2007
Filed:
Aug. 27, 2004
Yu Du, Blacksburg, VA (US);
Michael A. Vaudrey, Blacksburg, VA (US);
Yu Du, Blacksburg, VA (US);
Michael A. Vaudrey, Blacksburg, VA (US);
Adaptive Technologies, Inc., Blacksburg, VA (US);
Abstract
A microphone housing improves the broadband noise canceling performance of an active noise canceling microphone system while also ensuring improved speech transmission through the system. First and second microphone elements are selected each having a diameter 'd' and a thickness 't'. The two microphone elements are aligned axially with the back surfaces in contact and secured in an axially aligned cylindrical cavity within a cylindrically shaped housing. The cylindrically shaped housing has an outside diameter “D,” an interior cavity of diameter of “d,” and a height “2t”. The housing is exposed to an environment comprising both speech and noise. The first microphone element is adapted to receive a signal having both voice and noise components, while the second microphone element is adapted to receive a signal that is predominantly noise. A controller processes signals from the first microphone element and the second microphone element. The values of D and d are selected so to obtain a ratio of D over d between 1 and about 2.4 or a near field power difference of the first microphone signal and the second microphone signal between 8 dB and 11 dB. In the event the near field power difference is more than 11 dB, the outside diameter of the microphone housing “D” is reduced. In the event the near field power difference is less than 8 dB, the outside diameter of the microphone housing “D” is increased.