🤖 AI Summary
This paper investigates optimal code design for list reconstruction over multi-burst erasure channels, aiming to precisely characterize the trade-off among error-correction capability, read complexity, and list size. Methodologically, it establishes the first tight error-ball bound under the burst metric; derives a Johnson-type lower bound via Kahn’s theorem and a novel upper bound based on a variant of Kleitman’s theorem; and improves the Gilbert–Varshamov bound for multi-burst settings. Leveraging combinatorial design, hypergraph matching, and discrete geometric techniques, the authors construct an efficient list-reconstruction algorithm with provable guarantees: achieving $O(n^lambda)$-list decoding with $Theta(n^
ho)$ reads, subject to $t-1 = varepsilon +
ho + lambda$, and determining the minimum redundancy achievable under polynomial read complexity. The results provide both tight theoretical bounds and constructive schemes for high-fault-tolerance, low-overhead data recovery.
📝 Abstract
We study optimal reconstruction codes over the multiple-burst substitution channel. Our main contribution is establishing a trade-off between the error-correction capability of the code, the number of reads used in the reconstruction process, and the decoding list size. We show that over a channel that introduces at most $t$ bursts, we can use a length-$n$ code capable of correcting $epsilon$ errors, with $Theta(n^
ho)$ reads, and decoding with a list of size $O(n^lambda)$, where $t-1=epsilon+
ho+lambda$. In the process of proving this, we establish sharp asymptotic bounds on the size of error balls in the burst metric. More precisely, we prove a Johnson-type lower bound via Kahn's Theorem on large matchings in hypergraphs, and an upper bound via a novel variant of Kleitman's Theorem under the burst metric, which might be of independent interest. Beyond this main trade-off, we derive several related results using a variety of combinatorial techniques. In particular, along with tools from recent advances in discrete geometry, we improve the classical Gilbert-Varshamov bound in the asymptotic regime for multiple bursts, and determine the minimum redundancy required for reconstruction codes with polynomially many reads. We also propose an efficient list-reconstruction algorithm that achieves the above guarantees, based on a majority-with-threshold decoding scheme.