This work studies the problem of secure connection in cooperative wireless communication with two relay strategies, decode-and-forward (DF) and randomize-and-forward (RF). The four-node scenario and cellular scenario are considered. For the typical four-node (source, destination, relay, and eavesdropper) scenario, we derive the optimal power allocation for the DF strategy and find that the RF strategy is always better than the DF to enhance secure connection. In cellular networks, we show that without relay, it is difficult to establish secure connections from the base station to the cell edge users. The effect of relay placement for the cell edge users is demonstrated by simulation. For both scenarios, we find that the benefit of relay transmission increases when path loss becomes severer. Index Terms-Relay placement, physical layer security, secure connection, outage.
The authors in REF investigated the optimal location of the relay to achieve secrecy connectivity for DF and randomize-and-forward (RaF) relaying scenarios.
Relay Placement for Physical Layer Security: A Secure Connection Perspective
IEEE Communications Letters
IEEE Communications Letters
Mathematics Computer Science