Error correction systems with modified Viterbi decoding

Patent 5539757 Issued on July 23, 1996. Estimated Expiration Date:

December 22, 2013. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

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Inventors

Assignee

AT&T Corp.

Application

No. 173818 filed on 12/22/1993

US Classes:

714/795Viterbi decoding

Examiners

Primary: Envall, Roy N. Jr.
Assistant: Moise, Emmanuel L.

International Classes

G06F 011/10
H03M 013/12

Abstract

In a communications system, a convolutional encoder encodes data from a data source and a modified Viterbi decoder decodes the encoded data after the encoded dated passes through an error producing channel. The decoder calculates selected metric increments, known as kernel metric increments, for half the states, and selects survivor metrics for all states.