Exact Error Analysis and Energy-Efficiency Optimization of Regenerative Relay Systems with Spatial Correlation

TL;DR

This paper provides exact error rate analysis and energy optimization strategies for regenerative relay systems in correlated multipath fading environments, offering insights for designing energy-efficient low-power wireless networks.

Contribution

It derives exact and asymptotic error expressions for correlated Nakagami-m fading and develops an energy minimization framework with optimal power allocation.

Findings

Significant energy savings achievable with optimal power strategies.

Impact of spatial correlation and fading severity on system performance.

Effective design guidelines for low-energy wireless networks.

Abstract

Energy efficiency and its optimization constitute critical tasks in the design of low-power wireless networks. The present work is devoted to the error rate analysis and energy-efficiency optimization of regenerative cooperative networks in the presence of multipath fading under spatial correlation. To this end, exact and asymptotic analytic expressions are firstly derived for the symbol-error-rate of $M{-}$ary quadrature amplitude and $M{-}$ary phase shift keying modulations assuming a dual-hop decode-and-forward relay system, spatially correlated Nakagami${-}m$ multipath fading and maximum ratio combining. The derived expressions are subsequently employed in quantifying the energy consumption of the considered system, incorporating both transmit energy and the energy consumed by the transceiver circuits, as well as in deriving the optimal power allocation formulation for minimizing energy consumption under certain quality-of-service requirements. A relatively harsh path-loss model, that also accounts for realistic device-to-device communications, is adopted in numerical evaluations and various useful insights are provided for the design of future low-energy wireless networks deployments. Indicatively, it is shown that depending on the degree of spatial correlation, severity of fading, transmission distance, relay location and power allocation strategy, target performance can be achieved with large overall energy reduction compared to direct transmission reference.