Lecture 6 : The Elias - Bassalygo Bound

نویسنده

  • Matt Cary
چکیده

We currently know the following four bounds on rate as a function of relative distance, three of them upper bounds (which tell us what rate-distance combinations are impossible), and one lower bound (which tells us what rate-distance combinations we can achieve). In the following, R is the rate and δ the relative distance of a code. For example, a (n, k, d) code has R = k/n and δ = d/n. Hq(x) is the q-ary entropy function, Hq(x) = x logq ( (q − 1)/x ) + (1− x) logq ( 1/(1− x) ) .

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تاریخ انتشار 2006