Secure Communication With a Wireless-Powered Friendly Jammer

• Published in: IEEE transactions on wireless communications Vol. 15; no. 1; pp. 401 - 415
• Main Authors: Wanchun Liu, Xiangyun Zhou, Durrani, Salman, Popovski, Petar
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2016; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Batteries; Communication system security; cooperative jamming; Energy harvesting; Energy use; Exact solutions; friendly jammer; Jammers; Jamming; Mathematical analysis; Mathematical models; Physical layer security; Power transfer; Protocols; Throughput; Upper bounds; Wireless communication; wireless power transfer; friendly jammer; Physical layer security; wireless power transfer; throughput; cooperative jamming
• ISSN: 1536-1276; 1558-2248
• DOI: 10.1109/TWC.2015.2474378

In this paper, we propose using a wireless-powered friendly jammer to enable secure communication between a source node and destination node, in the presence of an eavesdropper. We consider a two-phase communication protocol with fixed-rate transmission. In the first phase, wireless power transfer is conducted from the source to the jammer. In the second phase, the source transmits the information-bearing signal under the protection of a jamming signal sent by the jammer using the harvested energy in the first phase. We analytically characterize the long-term behavior of the proposed protocol and derive a closed-form expression for the throughput. We further optimize the rate parameters for maximizing the throughput subject to a secrecy outage probability constraint. Our analytical results show that the throughput performance differs significantly between the single-antenna jammer case and the multiantenna jammer case. For instance, as the source transmit power increases, the throughput quickly reaches an upper bound with single-antenna jammer, while the throughput grows unbounded with multiantenna jammer. Our numerical results also validate the derived analytical results.