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On Unordered Codes
February 1991 (vol. 40 no. 2)
pp. 125-131

By extending the results obtained by D. E. Knuth (1986), a parallel unordered coding scheme with 2/sup r/ information bits is described. Balanced codes in which each codeword contains equal amounts of zeros and ones, with r check bits and up to 2/sup r+1/-(r+2) information bits, are constructed. Unordered codes with r check bits and up to 2/sup r/+2/sup r-1/-1 information bits are designed. Codes capable of detecting 2/sup r-1/+(2/sup r//2)-1 unidirectional errors using r check bits are also described. A review of previous work is presented.

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Index Terms:
unordered codes; parallel unordered coding scheme; zeros; ones; unidirectional errors; encoding; error correction codes.
B. Bose, "On Unordered Codes," IEEE Transactions on Computers, vol. 40, no. 2, pp. 125-131, Feb. 1991, doi:10.1109/12.73583
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