Weaknesses of Margulis and Ramanujan-Margulis Low-Density Parity-Check Codes
نویسندگان
چکیده
منابع مشابه
Weaknesses of Margulis and Ramanujan-Margulis low-density parity-check cCodes
We report weaknesses in two algebraic constructions of low-density parity-check codes based on expander graphs. The Margulis construction gives a code with nearcodewords, which cause problems for the sum-product decoder; The RamanujanMargulis construction gives a code with low-weight codewords, which produce an error-floor.
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ژورنال
عنوان ژورنال: Electronic Notes in Theoretical Computer Science
سال: 2003
ISSN: 1571-0661
DOI: 10.1016/s1571-0661(04)80768-0