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. 01, 2001
Filed:
Oct. 20, 1999
Hamid R. Sadjadpour, West Caldwell, NJ (US);
AT&T Corp., New York, NY (US);
Abstract
The present invention provides a method, computer medium, firmware, and device for minimizing memory requirements for computations for decoding using Maximum Likelihood Probability MAP-based decoding. The method includes the steps of: computing corresponding alpha &agr; values and beta &bgr; values simultaneously and storing in memory said alpha &agr; values and beta &bgr; values computed for &agr; at time k=1,2, . . ., N/2 and &bgr; at time k=N, . . . , (N/2)+1; and computing soft output data for alpha at time k=(N/2)+i and beta at time (N/2)−i+1, i being a positive integer, for,and,, wherein &agr; and &bgr; are parameter values computed by forward and backward recursion, respectively, based on transition probabilities of a selected channel and on input binary data at discrete time k and a parity bit corresponding to one of: a first recursive systematic convolutional encoder and a second recursive systematic convolutional encoder.