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. 25, 1996
Filed:
Mar. 09, 1994
Horng-Dar Lin, Holmdel, NJ (US);
AT&T Corp., Murray Hill, NJ (US);
Abstract
The present invention provides a method and apparatus for decoding data which has been encoded using high rate trellis codes, such as rate-k/n convolutional codes. The method of the present invention includes assigning code states to each of a plurality of decoder processing elements; scheduling computation of a plurality of new path metrics within the processing elements using previously-computed path metrics and branch metrics which vary with the encoded data; scheduling access for each of the processing elements to an appropriate set of the previously-computed metrics, such that each of the previously-computed metrics in the appropriate set is accessed in series by a given processing element in order to compute the new path metrics; and using a survivor sequence of path metrics computed in accordance with the scheduling steps to estimate the uncoded data. The path metrics may be efficiently reordered as they are computed to facilitate access thereto for subsequent path metric computation.