Core Concepts
Two infinite classes of constacyclic codes are constructed and analyzed, one of which contains ternary negacyclic self-dual codes with very good minimum distance properties.
Abstract
The paper presents two main contributions:
Two infinite classes of constacyclic codes C are constructed such that the minimum distances d(C) and d(C⊥) both have very good lower bounds.
Two infinite classes of ternary negacyclic self-dual codes with square-root-like lower bounds on their minimum distances are obtained.
The first class of constacyclic codes C(1,n) are ternary negacyclic self-dual codes with excellent parameters. For example, when m=4, C(1,40) is a ternary [40,20,9] self-dual code, which has better minimum distance than the best known ternary self-dual [40,20,12] code.
The second class of constacyclic codes C(q,m,ℓ) are analyzed in detail. Their dimensions and minimum distances are lower bounded. It is shown that for certain parameters, these codes have optimal or best known parameters.
The key techniques used include:
Splitting the defining set Ω(1)(r,n) based on Hamming weight to construct the first class of negacyclic codes.
Leveraging the structure of projective Reed-Muller codes to construct and analyze the second class of constacyclic codes.
Applying the constacyclic BCH bound to lower bound the minimum distances.