Soft-decision decoding is an NP-hard problem with great interest to developers of communication systems. We present an efficient soft-decision decoder of linear block codes based on compact genetic algorithm (cGA) and compare its performances with various other decoding algorithms including Shakeel algorithm. The proposed algorithm uses the dual code in contrast to Shakeel algorithm which uses ...

We determine the dimension and in some cases the minimum distance of primitive, narrow sense BCH codes of length n with small designed distance. We show that such a code contains its Euclidean dual code and, when the size of the field is a perfect square, also its Hermitian dual code. We establish two series of quantum error-correcting codes.

The weight distribution of the binary self-dual [128, 64] code being the extended code C of the code C spanned by the incidence vectors of the blocks of the polarity design in PG(6, 2) [11] is computed. It is shown also that R(3, 7) and C have no self-dual [128, 64, d] neighbor with d ∈ {20, 24}.

Two families of complementary codes over finite fields q are studied, where 2 = q r is square: i) Hermitian complementary dual linear codes, and ii) trace Hermitian complementary dual subfield linear codes. Necessary and sufficient conditions for a linear code (resp., a subfield linear code) to be Hermitian complementary dual (resp., trace Hermitian complementary dual) are determined. Construct...

Using [52, 26, 10] binary self-dual codes, possesing an automorphism of order 3, we construct new [54, 27, 10] binary self-dual codes. We do this by applying a technique for extending a [2k, k, d] self-dual code to a [2k+2, k+1] self-dual code. Most of the constructed codes have new values of the parameter in their weight numerators,. We construct new codes with   20, 21, 22 for the first wei...

In [9], the codewords of small weight in the dual code of the code of points and lines of Q(4, q) are characterised. Inspired by this result, using geometrical arguments, we characterise the codewords of small weight in the dual code of the code of points and generators ofQ(5, q) andH(5, q), and we present lower bounds on the weight of the codewords in the dual of the code of points and k-space...