Ergodic Secrecy Rate of Optimal Source Selection in a Multi-Source System with Unreliable Backhaul

TL;DR

This paper derives a closed-form expression for the ergodic secrecy rate of optimal source node selection in multi-source wireless systems with unreliable backhaul, considering multiple eavesdroppers and fading channels.

Contribution

It provides a generalized closed-form solution for the ergodic secrecy rate in various optimal selection scenarios, including source, relay, and transmit antenna selection.

Findings

Closed-form ESR expression for multi-source systems with eavesdroppers.

High SNR approximation simplifies ESR to a weighted sum of source contributions.

Backhaul unreliability impacts the secrecy performance significantly.

Abstract

The use of multiple source nodes with wireless backhaul is considered for secrecy enhancement through source node selection in future wireless networks. The ergodic secrecy rate (ESR) of {optimal source node selection in the presence of multiple eavesdroppers} over independent non-identically distributed (INID) Rayleigh fading channels is evaluated in closed-form. At high signal-to-noise ratio (SNR), {the ESR is expressed as a simple weighted summation where each term relates to the contribution of an individual source and eavesdropper}. An asymptotic analysis shows the effect of the system parameters and backhaul reliability on the performance. {The proposed method can provide a generalized solution for the ESR of optimal \textit{transmit antenna} selection in multi-antenna systems, optimal \textit{source node} selection, and optimal \textit{relay selection} with or without unreliable backhaul.