Effects of Relay Selection Strategies on the Spectral Efficiency of Wireless Systems with Half- and Full-duplex Nodes

TL;DR

This paper develops an analytical framework combining renewal theory and stochastic geometry to evaluate relay selection strategies in half- and full-duplex wireless networks, revealing their performance dependencies on self-interference and relay type.

Contribution

It introduces a novel analytical approach to compare relay selection strategies in half- and full-duplex wireless systems using stochastic geometry and renewal theory.

Findings

Fixed relay outperforms reactive relay in both duplex modes.

Performance depends on self-interference attenuation in full-duplex.

Reactive relay suffers from hop-based relay selection, fixed relay benefits from full-duplex.

Abstract

This work proposes an analytical framework to study how relay selection strategies perform in half- and full-duplex deployments by combining renewal theory and stochastic geometry. Specifically, we assume that the network nodes -- operating in either half- or full-duplex mode -- are scattered according to a two-dimensional homogeneous Poisson point process to compute the relay selection cost by using a semi-Markov process. Our results show: ($i$) fixed relay outperforms the reactive option in either cases, ($ii$) the performance of both reactive and fixed relay strategies depends on the self-interference attenuation in full-duplex scenarios, evincing when they outperform the half-duplex option, and ($iii$) the reactive relay selection suffers from selecting relays at hop basis, while the fixed relay selection benefits most from the full-duplex communication.