Twisting geometric codes
نویسندگان
چکیده
The aim of this paper is to explain how, starting from a Goppa code C(X,G, P1, ..., Pn) and a cyclic covering π : Y → X of degree m, one can twist the initial code to another one C(X,G + Dχ, P1, ..., Pn), where Dχ is a non-principal degree 0 divisor on X associated to a character χ of Gal(Y/X), in the hope that `X(G + Dχ) > `X(G). We give, using a MAGMA program, several examples where this occurs, and where both the initial and twisted codes have same minimum distance, so that initial codes have been improved.
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عنوان ژورنال:
- Finite Fields and Their Applications
دوره 14 شماره
صفحات -
تاریخ انتشار 2008