66 research outputs found
On the weight distributions of several classes of cyclic codes from APN monomials
Let be an odd integer and be an odd prime. % with ,
where is an odd integer.
In this paper, many classes of three-weight cyclic codes over
are presented via an examination of the condition for the
cyclic codes and , which have
parity-check polynomials and respectively, to
have the same weight distribution, where is the minimal polynomial of
over for a primitive element of
. %For , the duals of five classes of the proposed
cyclic codes are optimal in the sense that they meet certain bounds on linear
codes. Furthermore, for and positive integers such
that there exist integers with and satisfying , the value
distributions of the two exponential sums T(a,b)=\sum\limits_{x\in
\mathbb{F}_{p^m}}\omega^{\Tr(ax+bx^e)} and S(a,b,c)=\sum\limits_{x\in
\mathbb{F}_{p^m}}\omega^{\Tr(ax+bx^e+cx^s)}, where , are
settled. As an application, the value distribution of is utilized to
investigate the weight distribution of the cyclic codes
with parity-check polynomial . In the case of and
even satisfying the above condition, the duals of the cyclic codes
have the optimal minimum distance
The weight distribution of a class of p-ary cyclic codes
AbstractFor an odd prime p and two positive integers n⩾3 and k with ngcd(n,k) being odd, the paper determines the weight distribution of a class of p-ary cyclic codes C over Fp with nonzeros α−1, α−(pk+1) and α−(p3k+1), where α is a primitive element of Fpn
New Combinatorial Construction Techniques for Low-Density Parity-Check Codes and Systematic Repeat-Accumulate Codes
This paper presents several new construction techniques for low-density
parity-check (LDPC) and systematic repeat-accumulate (RA) codes. Based on
specific classes of combinatorial designs, the improved code design focuses on
high-rate structured codes with constant column weights 3 and higher. The
proposed codes are efficiently encodable and exhibit good structural
properties. Experimental results on decoding performance with the sum-product
algorithm show that the novel codes offer substantial practical application
potential, for instance, in high-speed applications in magnetic recording and
optical communications channels.Comment: 10 pages; to appear in "IEEE Transactions on Communications
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