Security Enhancement for Energy Harvesting Cognitive Networks with Relay Selection

Abstract

Relay selection is proposed in this paper as an efficient solution to secure information transmission of secondary users against eavesdroppers in energy harvesting cognitive networks. The proposed relay selection method selects a secondary relay among available secondary relays, which are capable of harvesting radio frequency energy in signals of the secondary transmitter and correctly restore secondary message, to curtail signal-to-noise ratio at the wire-tapper. In order to evaluate the security performance of the suggested relay selection method, an exact intercept outage probability formula accounting for peak transmit power confinement, Rayleigh fading, and interference power confinement is firstly derived. Monte-Carlo simulations are then generated to corroborate the proposed formula. Numerous results expose that positions of relays, the number of relays, and parameters of the energy harvesting method significantly influence the security performance while the power confinements on secondary transmitters cause the performance saturation.

Impact of Channel Estimation-and-Artificial Noise Cancellation Imperfection on Artificial Noise-Aided Energy Harvesting Overlay Networks

“…As such, the SINRs at E for recovering x s and x p are inferred from (12). Inserting (6) into (12) results in…”

“…CRs (Cognitive Radios), which typically operate in overlay, underlay, and interweave modes, can access the licensed frequency band of PUs (Primary Users) without causing any performance degradation for PUs, thus significantly improving spectral efficiency and mitigating spectrum scarcity issue [6]. In the underlay mode, CRs utilize the licensed spectrum but must upperbound interference caused at PUs.…”

Relay Selection for Security Improvement in Cognitive Radio Networks with Energy Harvesting

“…Previous Works. While most recent publications focused on securing direct transmission (i.e., without relaying [17][18][19][20][21][22][23]) and relaying transmission (i.e., without relay selection [24][25][26][27][28]) in cognitive radio networks with energy harvesting (CRNwEH) by the physical layer security technique (e.g., [29][30][31][32][33]), to the best of our understanding only three works in [34][35][36] mentioned the relay selection in these networks. To be specific, [34] studied the security capability of the conventional reactive relay selection in CRNwEH in terms of the secrecy outage probability (SOP) through Monte-Carlo simulations under the (peak transmission and interference) power constraints.…”

“…Furthermore, [35] solely analyzed the connection outage probabilities (The connection outage probability indicates the possibility that the received SNR is smaller than a target value) of the wire-tapper and the unlicensed destination. Recently, ( [37] is the conference version of [36]. In [37], a part of the results of [36] was briefly presented without any proof.…”

“…Recently, ( [37] is the conference version of [36]. In [37], a part of the results of [36] was briefly presented without any proof. However, the direct link was considered in [37] but not in [36]) [36] suggested a relay selection method where the adopted relay must successfully recover the unlicensed source's information and minimize the SNR at the wire-tapper.…”