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:
Oct. 11, 2005
Filed:
Apr. 19, 2000
Applicant:
Richard G. C. Williams, San Diego, CA (US);
Inventor:
Richard G. C. Williams, San Diego, CA (US);
Assignee:
3Com Corporation, Marlborough, MA (US);
Primary Examiner:
Int. Cl.
CPC ...
H04B001/38 ;
U.S. Cl.
CPC ...
Abstract
A differential encoder is designed to correct for any phase invariance. Without differential encoding defined for the V.92 upstream, undetectable errors are possible in a modem due to an inversion in the upstream channel. Immunity to channel inversions is provided by differentially encoding a combined preceding and modulus conversion system. A frame of a constellations is attributed a sign and the frame and the sign are differentially encoded. The frame and the sign are differentially decoded after the multiple modulus decoder, ensuring phase shift immunity.