Good Quasi-Cyclic Codes from Circulant Matrices Concatenation using a Heuristic Method
نویسندگان
چکیده
In this paper we present a method to search q circulant matrices; the concatenation of these circulant matrices with circulant identity matrix generates quasi-cyclic codes with high various code rate q/(q+1) (q an integer). This method searches circulant matrices in order to find the good quasi-cyclic code (QCC) having the largest minimum distance. A modified simulated annealing algorithm is used as an evaluator tool of the minimum distance of the obtained QCC codes. Based on this method we found 16 good quasi-cyclic codes with rates (1/2, 2/3 and 3/4), their estimated minimum distance reaches the lower bounds of codes considered to be the better linear block codes in Brouwer’s database. Keywords—Circulant matrix; quasi-cyclic Codes; Minimum Distance; Simulated Annealing; Linear Error Correcting codes
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