Physical Layer Security Schemes for Two-Way Cooperative Network with Multiple Eavesdroppers

Physical layer security has been taken a considerable attention for several years due to the broadcasting nature of the wireless networks. In this work, the relay and jammers selection in two-way cooperative networks are considered to improve the physical layer security. Three different categories of selection schemes are proposed including selection schemes without jamming, selection schemes with conventional jamming and selection schemes with controlled jamming. After that, two techniques are proposed to increase the secrecy rate in two-way cooperative networks: firstly, artificial noise is used to confuse eavesdropper: This signal is sent from intermediate nodes. As a result, the total secrecy rate is increased. Secondly, we propose a sub-optimal power allocation solution for jammer nodes. Sub-optimal power of the jammer nodes vary according to the type of scenario, location of the eavesdroppers and the second source. The sub-optimal power allocation to the jammer nodes causes more eavesdroppers confusion. As a result, the total secrecy rate is increased too. We also compare the secrecy rate in one-way cooperative networks and proposed two-way cooperative network. Therefore improving in secrecy rate in two-way relay networks are observed clearly. In total, simulation and analytical results demonstrate the performance improvement of the proposed techniques.

Keywords:

Physical layer security , artificial noise , Power allocation , secrecy rate