Codes for symbol-pair read channels

A new coding framework is established for channels whose outputs are overlapping pairs of symbols. Such channels are motivated by storage applications in which the spatial resolution of the reader may be lower than that of the process that was used to store the data. Reading symbols as pairs changes the error model from the standard bounded number of symbol errors to a bounded number of pair errors. Starting from the most basic coding-theoretic questions, the paper studies codes that protect against pair-errors. It provides answers on pair-error correctability, code construction and decoding, and lower and upper bounds on code sizes.