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The Forney Algorithm for Computing the Error Magnitudes

First, define an infinite-degree syndrome polynomial

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Then, define the error magnitude polynomial as follows:

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Given that we know only the first 2t coefficients of S(x), the decoding problem becomes one of finding a polynomial tex2html_wrap_inline464 of degree less than or equal to t that satisfies

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The error magnitudes are computed using the expression

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Example: Double-error correction using the Berlekamp algorithm and a (7,3) Reed-Solomon code



A. Matache
Sun Oct 20 17:42:25 PDT 1996