Group-Decodable Space-Time Block Codes with Code Rate > 1

TL;DR

This paper introduces systematic methods for constructing high-rate, group-decodable space-time block codes that achieve full diversity and significantly reduce decoding complexity in MIMO systems.

Contribution

It provides a novel systematic approach to design high-rate, group-decodable STBCs with full diversity for any number of transmit antennas and code length.

Findings

Achieves near-linear increase in code rate with transmit antennas.

Reduces decoding complexity compared to existing codes.

Maintains full symbol-wise diversity gain.

Abstract

High-rate space-time block codes (STBC with code rate > 1) in multi-input multi-output (MIMO) systems are able to provide both spatial multiplexing gain and diversity gain, but have high maximum likelihood (ML) decoding complexity. Since group-decodable (quasi-orthogonal) code structure can reduce the decoding complexity, we present in this paper systematic methods to construct group-decodable high-rate STBC with full symbol-wise diversity gain for arbitrary transmit antenna number and code length. We show that the proposed group-decodable STBC can achieve high code rate that increases almost linearly with the transmit antenna number, and the slope of this near-linear dependence increases with the code length. Comparisons with existing low-rate and high-rate codes (such as orthogonal STBC and algebraic STBC) are conducted to show the decoding complexity reduction and good code performance achieved by the proposed codes.