Method and system for estimating an input data sequence based on an output data sequence and hard disk drive incorporating same

摘要

A method for generating an updated path metric includes combining each of first and second provisional path metric first portions with an associated branch metric first portion to produce a first provisional updated path metric first portion candidate and a second provisional updated path metric first portion candidate, respectively. The method also includes selecting one of the provisional first portion updated path metric candidates to produce an updated path metric first portion candidate and combining any carry component of the selected updated path metric first portion candidate with a path metric second portion and a branch metric second portion to produce a first updated path metric second portion candidate. The method also includes comparing the updated path metric second portion candidate to at least one other updated path metric second portion candidate; and selecting one of the updated path metric second portion candidates to produce an updated path metric second portion.