Achieving physical-layer secrecy via friendly jamming with dynamic role assignment for coordinating transmitters

This paper proposes a novel physical-layer security scheme for anti-eavesdropping, which is based on friendly jamming with dynamic role assignment (DRA). In particular, the roles of message sender and cooperative jammer could be adaptively re-assigned among multiple coordinating transmitter nodes to enhance secrecy rate. We discuss two different prospect approaches to determine the role assignment patterns, including exhaustive search and a reduced-complexity method invoking Hungarian algorithm. Furthermore, by treating all coordinating transmission nodes as a single virtual entity, the paper also examines DRA-based cooperative jamming for reconfigurable antenna groups, which provides a much higher adaptation flexibility and hence superior security performance.