Local Rank Modulation for Flash Memories

摘要

Local rank modulation (LRM) scheme was suggested for representing the information in Hash memories in order to overcome the drawbacks of rank modulation. For 0 < s <= t <= n with s dividing n, an (s, t, n)-LRM scheme is a LRM scheme where the n cells are locally viewed cyclically through a sliding window of size t resulting in a sequence of small permutations, which requires less comparisons and less distinct values. The gap between two such windows equals to s. In this paper, encoding, decoding, and asymptotic enumeration of the (1, t, n)-LRM scheme are studied.