Error Rate and Power Allocation Analysis of Regenerative Networks under Generalized Fading Conditions

TL;DR

This paper analyzes the end-to-end error performance and optimal power allocation of regenerative multi-relay cooperative networks operating over generalized fading channels, providing new analytical expressions and demonstrating significant performance improvements.

Contribution

It introduces novel closed-form expressions for symbol-error-rate over non-homogeneous fading channels and formulates a power optimization strategy for enhanced system performance.

Findings

Optimal power allocation significantly improves error performance.

Derived expressions match simulation results accurately.

Performance gains are notable in unbalanced relay link scenarios.

Abstract

Cooperative communication has been shown to provide significant increase of transmission reliability and network capacity while expanding coverage in cellular networks. The present work is devoted to the investigation of the end-to-end performance and power allocation of a maximum-ratio-combining based regenerative multi-relay cooperative network over non-homogeneous scattering environment, which is the case in realistic wireless communication scenarios. Novel analytic expressions are derived for the end-to-end symbol-error-rate of both $M-$ary Phase-Shift Keying and $M-$ary Quadrature Amplitude Modulation over independent and non-identically distributed generalized fading channels. The offered results are expressed in closed-form involving the Lauricella function and can be readily evaluated with the aid of a proposed computational algorithm. Simple expressions are also derived for the corresponding symbol-error-rate at asymptotically high signal-to-noise ratios. The derived expressions are corroborated with respective results from computer simulations and are subsequently employed in formulating a power optimization problem that enhances the system performance under total power constraints within the multi-relay cooperative system. Furthermore, it is shown that optimum power allocation provides substantial performance gains over equal power allocation, particularly, when the source-relay and relay-destination paths are highly unbalanced.