A lifting method to replace factorization in Sudan's algorithm.


Daniel Augot

INRIA, projet CODES
BP 105
78153 Le Chesnay Cedex, France
Daniel.Augot@inria.fr

Lancelot Pecquet
INRIA, projet CODES
BP 105
78153 Le Chesnay Cedex, France
Lancelot.Pecquet@inria.fr

IEEE Transactions on Information Theory, 46(7):2605-2614, November 2000.


Abstract

This correspondence presents an algorithmic improvement to Sudan's list-decoding algorithm for Reed Solomon codes and its generalization to algebraic geometric codes from Shokrollahi and Wasserman. Instead of completely factoring the interpolation polynomial over the function field of the curve, we compute sufficiently many coefficients of a Hensel development to reconstruct the functions that correspond to codewords. We prove that these Hensel developments can be found efficiently using Newton s method. We also describe the algorithm in the special case of Reed Solomon codes.

Keywords

Algebraic geometric codes, Hensel lifting, list decoding, Newton s method, polynomials over algebraic function fields, Reed Solomon codes.