Non-binary Two-Deletion Correcting Codes and Burst-Deletion Correcting Codes

In this paper, we construct systematic $q$-ary two-deletion correcting codes and burst-deletion correcting codes, where $q\geq 2$ is an even integer. For two-deletion codes, our construction has redundancy $5\log n+O(\log q\log\log n)$ and has encoding complexity near-linear in $n$, where $n$ is the length of the message sequences. For burst-deletion codes, we first present a construction of binary codes with redundancy $\log n+9\log\log n+\gamma_t+o(\log\log n)$ bits $(\gamma_t$ is a constant that depends only on $t)$ and capable of correcting a burst of at most $t$ deletions, which improves the Lenz-Polyanskii Construction (ISIT 2020). Then we give a construction of $q$-ary codes with redundancy $\log n+(8\log q+9)\log\log n+o(\log q\log\log n)+\gamma_t$ bits and capable of correcting a burst of at most $t$ deletions.