Single-Deletion Single-Substitution Correcting Codes
Ilia Smagloy, Lorenz Welter, Antonia Wachter-Zeh, Eitan Yaakobi
Abstract
Correcting insertions/deletions as well as substitution errors simultaneously plays an important role in DNA-based storage systems as well as in classical communications. This paper deals with the fundamental task of constructing codes that can correct a single insertion or deletion along with a single substitution. A non-asymptotic upper bound on the size of non-binary single-deletion <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$s$ </tex-math></inline-formula> -substitution correcting codes is derived, showing that the non-asymptotic redundancy of such a code of length <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$n$ </tex-math></inline-formula> has to be at least <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$(s+1) \log _{q} n$ </tex-math></inline-formula> . An explicit construction of binary single-deletion single-substitution correcting codes with at most <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$6 \log n + 8$ </tex-math></inline-formula> redundancy bits is presented.