Cooperative Secure Resource Allocation in Cognitive Radio Networks with Guaranteed Secrecy Rate for Primary Users

• Published in: IEEE transactions on wireless communications Vol. 13; no. 2; pp. 1058 - 1073
• Main Authors: Mokari, Nader, Parsaeefard, Saeedeh, Saeedi, Hamid, Azmi, Paeiz
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.02.2014; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Allocations; Applied sciences; Cognitive radio networks; ergodic and instantaneous resource allocation; Exact sciences and technology; generalized geometric programming (GPP); Interference; Jammers; Jamming; Networks; Optimization; Plutonium; Radio networks; Radiocommunication specific techniques; Radiocommunications; Receivers; Relay; Relays; Resource allocation; Resource management; Secret; secure communication; Signal to noise ratio; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Transmitters; Transmitters. Receivers; Performance evaluation; Parameter estimation; Relay; Power transmission; Resource allocation; Transmitter; Ergodicity; Algorithm; Power allocation; Jamming; Geometrical model; Optimization; secure communication; Simulation; ergodic and instantaneous resource allocation; Channel estimation; Resource management; Secrecy; Cognitive radio networks; generalized geometric programming (GPP); Radio communication; Telecommunication security; Software radio
• ISSN: 1536-1276; 1558-2248
• DOI: 10.1109/TWC.2013.010214.130929

In this paper, we introduce a new cooperative paradigm for secure communication in cognitive radio networks (CRNs) where secondary users (SUs) are allowed to access the spectrum of primary users (PUs) as long as they preserve the secure communication of PUs in the presence of malicious eavesdroppers. To do so, the SU transmission is divided into two hops: at first hop, the SU transmitter sends the information to a relay set and the SU receiver acts as a friendly jammer to disturb the overhearing of eavesdroppers and at the second hop, one of the relays is selected to pass the information to the SU receiver and the SU transmitter acts as a friendly jammer for the PU. In this new setup, the time duration for each hop, the power transmissions of all nodes in CRN, and relay selection at the second hop are allocated in such a way that the secrecy rate of the SU is maximized subject to the minimum required PU's secrecy rate. From primary service perspective, this transforms the possibly disturbing secondary service activities into a beneficial network element. We investigate instantaneous and ergodic resource allocation problems for perfect and imperfect channel state information (CSI). Since these problems are non-convex, we propose a solution based on decomposition of main optimization problem into three subproblems related to the power allocation, time allocation, and relay selection. We show that the power allocation problem can be transformed into a generalized geometric programming (GGP) model via the so-called scaled algorithm and it can be solved very efficiently. Simulation results indicate that in terms of the secondary secrecy rate, the proposed setup outperforms the conventional setup in which the secrecy rate of the PU is not guaranteed.