Physical layer security in wireless-powered networks with untrusted relays
Ying Cai, Chao Zhang
In this paper, we study the secrecy performance of a wirelessly powered relay-aided system, where a pair of legal users (source-destination) communicate in the presence of multiple untrusted relays. All of the nodes mentioned above are energy constrained and powered by a dedicated power beacon (PB). To prevent the untrusted relays from intercepting the source message and to achieve positive secrecy rate, the destination-based cooperative jamming technique is employed. Besides, the optimal time allocation coefficient to maximize the secrecy throughput and the optimal transmit power of PB to maximize the secrecy energy efficiency are addressed. Specifically, three relay selection schemes with various requirements for channel state information (CSI), i.e., random relay selection, partial relay selection and optimal relay selection are also proposed to enhance the system security further. Finally, simulation results indicate the cooperative jamming technique indeed achieve positive secrecy rate and the proposed optimization strategies can improve the system performance.
IEEE International Conference on Communication Technology (ICCT)•Oct 1, 2017•2 citations