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. 11, 1986
Filed:
Dec. 10, 1984
Applicant:
Inventor:
Gary D Martin, North Andover, MA (US);
Assignee:
AT&T Bell Laboratories, Murray Hill, NJ (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
371 43 ;
Abstract
A technique for improving efficiency of error-correction is disclosed for use in a Gray-coded multilevel transmission system and, specifically, in a quadrature amplitude modulation (QAM) transmission system. To this end, information bits in information bit symbols are converted, i.e., mapped, into error-correction bit symbols having fewer bits than the corresponding information bit symbols. This bit-converting technique permits use of encoders and decoders having a code rate lower than the overall transmission code rate.