REPUBLIC OF SERBIA

MINISTRY OF DEFENCE

www.mod.gov.rs

MINISTRY OF DEFENCE

Material Resources Sector

Defensive Technologies Department

Military Technical Institute

www.vti.mod.gov.rs

Analyzing decode-and-forward relaying strategy
in the presence of eavesdropping attack

DEJAN n. mILIĆ

University of Niš, Faculty of Electronic Engineering, Niš, dejan.milic@elfak.ni.ac.rs

DANIELA m. MILOVIĆ

University of Niš, Faculty of Electronic Engineering, Niš, daniela.milovic@elfak.ni.ac.rs

IVICA b. MARJANOVIĆ

Republic of Serbia Ministry of Defence, Belgrade, ivica.marjanovic@mod.gov.rs

JELENA a. ANASTASOV

University of Niš, Faculty of Electronic Engineering, Niš, jelena.anastasov@elfak.ni.ac.rs

ALEKSANDRA m. CVETKOVIĆ

University of Niš, Faculty of Electronic Engineering, Niš, aleksandra.cvetkovic@elfak.ni.ac.rs

Abstract: This paper studies the intercept behavior of decode-and-forward (DF) wireless relaying scheme over asymmetric fading channels. The system model is such that it assumes a line-of-sight propagation component from the source to relay, and non-line-of sight characteristics of the received signal at the destination. Under the given scenario, first hop of the DF scheme is subjected to the Rician fading, while the second hop experiences Rayleigh fading. An eavesdropper tries to overhear both phases of transmission, either transmission from the source to relay, either from the relay to destination. According to this scenario, we have derived expression for the probability that an intercept event may occur. Also, through numerical results, we have provided an insight into the impact of different channel conditions on physical layer security of the system under consideration.

Keywords: asymmetric fading channels, decode-and-forward relaying scheme, physical layer security, probability of intercept.