Open AccessAnalysis of security performance of relay selection in underlay cognitive networks
Author(s) -
HoVan Khuong,
DoDac Thiem
Publication year - 2018
Publication title -
iet communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.355
H-Index - 62
eISSN - 1751-8636
pISSN - 1751-8628
DOI - 10.1049/iet-com.2017.0445
Subject(s) - underlay , relay , computer science , selection (genetic algorithm) , computer network , cognitive radio , cognition , computer security , telecommunications , artificial intelligence , psychology , wireless , signal to noise ratio (imaging) , power (physics) , neuroscience , physics , quantum mechanics
Underlay cognitive networks allow unlicenced/secondary users (SUs) to opportunistically access licenced frequency bands, and hence information transmission is undoubtedly wire‐tapped by eavesdroppers. This study analyses security performance of a relay selection scheme, which selects a secondary relay to minimise information wire‐tapping of eavesdroppers, in underlay cognitive networks. Toward this end, the authors propose approximate and asymptotic intercept outage probability expressions which account for interference power constraint for licenced/primary users, maximum transmit power constraint for SUs, independent non‐identical fading channels, and direct channel between secondary source and eavesdropper. Moreover, they determine diversity order and coding gain of this relay selection based on the proposed asymptotic expression. Monte Carlo simulations validate these expressions and numerous results demonstrate that the investigated relay selection prevents the eavesdropper from obtaining full diversity order offered by all relays and source, induces the intercept outage probability saturated at either large maximum transmit power or large maximum interference power, and improves information security performance with respect to the increase in the number of relays.