Physical Layer Security in Distributed Wireless Networks Using Full-Duplex Receiver Jamming

In this paper, we study the benefits of full-duplex (FD) receiver jamming in enhancing physical layer security for a two-tier heterogeneous distributed wireless network, with each tier deployed with multiple pairs of a single-antenna transmitter (Tx) and a multi-antenna receiver (Rx). In the first tier, each Tx sends unclassified information and each Rx works in the half-duplex (HD) mode just receiving the desired signal. In the second tier, each Tx deliveries confidential information and each Rx works in the FD mode simultaneously receiving the desired signal and radiating a jamming signal to confuse randomly located multi-antenna eavesdroppers. We analyze the connection probability and the secrecy outage probability for a typical FD Rx, and then determine the optimal density of the FD tier that maximizes network-wide secrecy throughput while satisfying a minimum required network-wide throughput for the HD tier. Numerical results are demonstrated to verify our theoretical findings and show that network-wide secrecy throughput is significantly improved by properly deploying the FD tier.