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:
May. 03, 1988
Filed:
Apr. 04, 1986
Applicant:
Inventors:
Thomas F Quatieri, Jr, Lexington, MA (US);
Gerald C O'Leary, Lexington, MA (US);
Assignee:
Massachusetts Institute of Technology, Cambridge, MA (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04B / ;
U.S. Cl.
CPC ...
370 321 ; 379410 ;
Abstract
A method for eliminating echos in modems used for full-duplex data communication is disclosed. The technique improves the cancellation of the echos by synthesizing an estimate of the desired signal and subtracting this estimate from the received waveform to improve the estimate of the residual echo. An adaptive filter is used to match the transmitted bit pattern to make an estimate of the frequency offset in the far echo, so that it can be cancelled more accurately.