Covering radius, codimension, and dual-distance width

Upper bounds on the covering radius of codes with a given cardinality and a given dual-distance width are derived. Using an entirely new method, some results published by C. Delorme and P. Sole (1991) for linear codes are generalized, and results are derived for unrestricted codes that have no previous analogue. For some classes of codes, when the parameters lie within certain intervals, results improve asymptotically on the upper bounds published by A.A. Tietavainen (1990) relating the covering radius with the dual distance.<
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