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:
Apr. 28, 2009
Filed:
Sep. 08, 2006
Peter J. Sallaway, San Diego, CA (US);
Sreen Raghavan, La Jolla, CA (US);
Peter J. Sallaway, San Diego, CA (US);
Sreen Raghavan, La Jolla, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A sequence detector (-) operating generally according to the Viterbi algorithm contains a branch metric generator (-), comparison circuitry (-), and symbol generation circuitry (, and) for converting digital values of a detector input signal into a sequence of predefined symbols chosen from an alphabet of predefined symbols. The comparison circuitry provides soft output signals for correcting errors. The soft output signals include best and second-best state metrics (p(i) and p(i)) and corresponding best and second-best comparison results (D(i) and D(i)). The symbol generation circuitry typically utilizes the best comparison results to generate a preliminary sequence of the predefined symbols, checks for error in the preliminary sequence, and utilizes the second-best comparison results in correcting any such error in the preliminary sequence so as to convert it into a final sequence of the predefined symbols.