A Novel Physical Layer Security Scheme for MIMO Two-Way Relay Channels

In this paper, we propose a novel secure transmission scheme for multiple-input multiple- output (MIMO) Two-Way relay channels, where multi- pair communication partners exchange information securely with the help of relay. By utilizing the properties of transmission medium in physical layer, our scheme can achieve high transmission efficiency as well as information theoretic security. With the secrecy capacity analysis, we show that our scheme is a secure approach under two different adversarial models: 1) untrusted relay attack model; 2) trusted relay with eavesdropper attack model. Finally, we conduct three simulations of our proposed scheme. The simulation results agree with the theoretical analysis illustrating that our proposed scheme can achieve a better performance than the existing schemes.