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:
Nov. 02, 1993
Filed:
Jul. 09, 1992
Rupert L Goodings, Cambridge, GB;
Gideon A Senensieb, Cambridge, GB;
Philip H Wilson, Surrey, GB;
Roy S Hansen, Dragor, DK;
GN Danavox AS, Taastrup, DK;
Abstract
A hearing aid includes a filter in an electrical feedback path, the characteristics of which filter are calculated to model acoustic coupling between the receiver and microphone of the aid. A limiter is inserted in the main electrical pathway between the microphone and the receiver to provide stability in the presence of sudden sound bursts. A noise signal is injected continuously into the electrical circuit and is used to adapt the characteristics of the filter to accommodate changes in the acoustic coupling. The level of the noise signal can be varied to match changes in residual signal level to maintain signal to noise ratio and to optimize rate of adaption commensurate with satisfactory hearing function while the noise itself is unobtrusive to the user.