A New Low-Complexity Decodable Rate-5/4 STBC for Four Transmit Antennas with Nonvanishing Determinants

TL;DR

This paper introduces a novel low-complexity, rate-5/4 full-diversity 4x4 STBC with non-vanishing determinants, offering improved performance and reduced complexity for wireless MIMO systems.

Contribution

It presents a new low-complexity decodable rate-5/4 STBC with NVD property, outperforming existing codes in performance and complexity metrics.

Findings

Better performance over Rayleigh fading channels

Lower average decoding complexity and PAPR

Slight increase in worst-case decoding complexity

Abstract

The use of Space-Time Block Codes (STBCs) increases significantly the optimal detection complexity at the receiver unless the low-complexity decodability property is taken into consideration in the STBC design. In this paper we propose a new low-complexity decodable rate-5/4 full-diversity 4 x 4 STBC. We provide an analytical proof that the proposed code has the Non-Vanishing-Determinant (NVD) property, a property that can be exploited through the use of adaptive modulation which changes the transmission rate according to the wireless channel quality. We compare the proposed code to the best existing low-complexity decodable rate-5/4 full-diversity 4 x 4 STBC in terms of performance over quasi-static Rayleigh fading channels, worst- case complexity, average complexity, and Peak-to-Average Power Ratio (PAPR). Our code is found to provide better performance, lower average decoding complexity, and lower PAPR at the expense of a slight increase in worst-case decoding complexity.