Construction of New Delay-Tolerant Space-Time Codes

TL;DR

This paper develops new delay-tolerant space-time codes based on cyclic division algebras, maintaining full diversity and optimal properties even under asynchronous transmission conditions.

Contribution

It introduces a novel construction of space-time codes that retain perfect code properties in asynchronous MIMO and cooperative networks.

Findings

Codes preserve full-diversity under delays

Maintain non-vanishing determinants in asynchronous scenarios

Achieve optimal DMT in delay-tolerant settings

Abstract

Perfect Space-Time Codes (STC) are optimal codes in their original construction for Multiple Input Multiple Output (MIMO) systems. Based on Cyclic Division Algebras (CDA), they are full-rate, full-diversity codes, have Non-Vanishing Determinants (NVD) and hence achieve Diversity-Multiplexing Tradeoff (DMT). In addition, these codes have led to optimal distributed space-time codes when applied in cooperative networks under the assumption of perfect synchronization between relays. However, they loose their diversity when delays are introduced and thus are not delay-tolerant. In this paper, using the cyclic division algebras of perfect codes, we construct new codes that maintain the same properties as perfect codes in the synchronous case. Moreover, these codes preserve their full-diversity in asynchronous transmission.