Ordered Covering Arrays and Upper Bounds on Covering Codes in NRT spaces

TL;DR

This paper introduces new constructions of ordered covering arrays and improves upper bounds on covering codes in NRT spaces, enhancing understanding of their structure and limits for larger alphabets.

Contribution

It presents novel recursive and direct methods for constructing ordered covering arrays and establishes improved upper bounds on covering codes in NRT spaces, extending previous results.

Findings

New constructions of ordered covering arrays using various techniques.

Improved upper bounds on covering codes in NRT spaces for larger alphabets.

Tables comparing new bounds with existing ones.

Abstract

This work shows several direct and recursive constructions of ordered covering arrays using projection, fusion, column augmentation, derivation, concatenation and cartesian product. Upper bounds on covering codes in NRT spaces are also obtained by improving a general upper bound. We explore the connection between ordered covering arrays and covering codes in NRT spaces, which generalize similar results for the Hamming metric. Combining the new upper bounds for covering codes in NRT spaces and ordered covering arrays, we improve upper bounds on covering codes in NRT spaces for larger alphabets. We give tables comparing the new upper bounds for covering codes to existing ones.