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:
Jun. 30, 1987
Filed:
Nov. 08, 1984
Hitachi, Ltd., Tokyo, JP;
Abstract
In an apparatus for decoding cyclic codes generated by a generator polynomial ##EQU1## (where P.sub.i (x) is a m.sub.i -order irreducible polynomial) including 0-th to l-th feedback shift registers corresponding to the terms (x.sup.c +1) and P.sub.i (x), a coincidence circuit for detecting coincidence of a predetermined number of low order bits of said 0-th to l-th feedback shift registers and all-zero conditions of a high order bits, the predetermined number being a minimum one of numbers of bits (c, m.sub.1, m.sub.2, . . . m.sub.l) of the feedback shift register, the 0-th feedback shift register having an output terminal thereof connected to an input terminal thereof, and the 1st to l-th feedback shift registers each having an output terminal thereof connected to an input terminal thereof and having exclusive OR gates inserted between stages determined by the associated simple polynomial, exclusive OR gates each receiving the output of the associated feedback shift register as one input thereto; a method for decoding the cyclic code for correcting a burst error by shifting the 0-th to l-th feedback shift registers until the coincidence circuit detects the coincidence, comprising the steps of; shifting at least one of said 0-th to l-th feedback shift registers a predetermined number of times; and simultaneously shifting the 0-th to l-th feedback shift registers after the predetermined number of shifting until the coincidence circuit detects the coincidence.