37 research outputs found
AG codes and AG quantum codes from the GGS curve
In this paper, algebraic-geometric (AG) codes associated with the GGS maximal
curve are investigated. The Weierstrass semigroup at all -rational points of the curve is determined; the Feng-Rao designed
minimum distance is computed for infinite families of such codes, as well as
the automorphism group. As a result, some linear codes with better relative
parameters with respect to one-point Hermitian codes are discovered. Classes of
quantum and convolutional codes are provided relying on the constructed AG
codes
Generalization of the Lee-O'Sullivan List Decoding for One-Point AG Codes
We generalize the list decoding algorithm for Hermitian codes proposed by Lee
and O'Sullivan based on Gr\"obner bases to general one-point AG codes, under an
assumption weaker than one used by Beelen and Brander. Our generalization
enables us to apply the fast algorithm to compute a Gr\"obner basis of a module
proposed by Lee and O'Sullivan, which was not possible in another
generalization by Lax.Comment: article.cls, 14 pages, no figure. The order of authors was changed.
To appear in Journal of Symbolic Computation. This is an extended journal
paper version of our earlier conference paper arXiv:1201.624
On quadratic residue codes and hyperelliptic curves
A long standing problem has been to develop "good" binary linear codes to be
used for error-correction. This paper investigates in some detail an attack on
this problem using a connection between quadratic residue codes and
hyperelliptic curves. One question which coding theory is used to attack is:
Does there exist a c<2 such that, for all sufficiently large and all
subsets S of GF(p), we have |X_S(GF(p))| < cp?Comment: 18 pages, no figure
Error Correcting Codes on Algebraic Surfaces
Error correcting codes are defined and important parameters for a code are
explained. Parameters of new codes constructed on algebraic surfaces are
studied. In particular, codes resulting from blowing up points in \proj^2 are
briefly studied, then codes resulting from ruled surfaces are covered. Codes
resulting from ruled surfaces over curves of genus 0 are completely analyzed,
and some codes are discovered that are better than direct product Reed Solomon
codes of similar length. Ruled surfaces over genus 1 curves are also studied,
but not all classes are completely analyzed. However, in this case a family of
codes are found that are comparable in performance to the direct product code
of a Reed Solomon code and a Goppa code. Some further work is done on surfaces
from higher genus curves, but there remains much work to be done in this
direction to understand fully the resulting codes. Codes resulting from blowing
points on surfaces are also studied, obtaining necessary parameters for
constructing infinite families of such codes.
Also included is a paper giving explicit formulas for curves with more
\field{q}-rational points than were previously known for certain combinations
of field size and genus. Some upper bounds are now known to be optimal from
these examples.Comment: This is Chris Lomont's PhD thesis about error correcting codes from
algebriac surface
Optimal curves of genus 1,2 and 3
In this survey, we discuss the problem of the maximum number of points of
curves of genus 1,2 and 3 over finite fieldsComment: 18 pages. To appear in "Publications Mathematiques de Besancon(PMB)