Efficient Systematic Deletions/Insertions of 0's Error Control Codes and the L_1 Metric (Extended version)
This paper gives some theory and efficient design of binary block systematic codes capable of controlling the deletions of the symbol “0” (referred to as 0-deletions) and/or the insertions of the symbol “0” (referred to as 0-insertions). The problem of controlling 0-deletions and/or 0-insertions (referred to as 0-errors) is known to be equivalent to the efficient design of L_1 metric asymmetric error control codes over the natural alphabet, ℕ. So, t 0-insertion correcting codes can actually correct t 0-errors, detect (t+1) 0-errors and, simultaneously, detect all occurrences of only 0-deletions or only 0-insertions in every received word (briefly, they are t-Symmetric 0-Error Correcting/(t+1)-Symmetric 0-Error Detecting/All Unidirectional 0-Error Detecting (t-Sy0EC/(t+1)-Sy0ED/AU0ED) codes). From the relations with the L_1 distance, optimal systematic code designs are given. In general, for all t,k∈ℕ, a recursive method is presented to encode k information bits into efficient systematic t-Sy0EC/(t+1)-Sy0ED/AU0ED codes of length n≤ k+tlog_2k+o(tlog n) as n∈ℕ increases. Decoding can be efficiently performed by algebraic means using the Extended Euclidean Algorithm (EEA).
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