Securing Multi-Antenna Two-Way Relay Channels With Analog Network Coding Against Eavesdroppers
This paper investigates the vulnerability of Analog Network Coding (ANC) to physical layer attacks from adversarial users, when all nodes are equipped with multiple antennas. Specifically, the authors examine the MIMO Two Way Relay Channel (TWRC) with two users trying to communicate with each other via a relay node in the presence of a passive eavesdropper. They propose a new performance metric, namely the secrecy sum rate of the MIMO TWRC, to quantify performance. They, then consider secure transmission strategies for the scenarios of no Eavesdropper Channel State Information at the Transmitters (ECSIT), partial ECSIT, and complete ECSIT, respectively. Finally, numerical results are presented to illustrate the improvement in secrecy obtained with the proposed transmission schemes.