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. 18, 2000
Filed:
Jun. 23, 1998
Thomas Harley, Columbia, MD (US);
Stephen Leese, St. Albans, GB;
Noise Cancellation Technologies, Inc., Linthicum, MD (US);
Abstract
A method and apparatus for cancelling acoustic echoes that enhances the hands free operation of audio/video conferencing equipment, wireless and cellular telephones, internet and intranet telephones, etc. is disclosed. The method and apparatus use a constrained and orthogonalized, frequency domain, block, least mean square adaptive filter to generate an estimate of an acoustic echo signal. The estimate of the acoustic echo signal is subtracted from a near end microphone signal to provide an echo reduced communication signal. The echo reduced communication signal is then either transmitted or processed further. The further processing can include non-linear processing using an adaptive speech filter. The method and apparatus include a novel method for updating the coefficients of an adaptive filter.