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:
Aug. 16, 1988
Filed:
Oct. 16, 1986
Applicant:
Inventors:
Claude Galand, Cagnes sur Mer, FR;
Guy Platel, Durham, NC (US);
Assignee:
International Business Machines Corp., Armonk, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04B / ;
U.S. Cl.
CPC ...
379411 ; 370 321 ;
Abstract
In a voice transmission network having an echo canceler including a flat delay line in series with an adaptive digital filter, a process is provided for adjusting the flat delay line length, thus enabling limiting the filter length to minimal value. The method is based on intercorrelation operations. It includes first intercorrelating sequences of energy values of blocks or consecutive samples, to derive a rough flat delay estimation therefrom; then intercorrelating sequences of signal samples with one of the sequences being roughly delayed, to derive therefrom an accurate flat delay estimation.