A Secure Transmission Scheme at The Receiver for Eavesdropping Prevention

In this paper, we suggest a physical layer security transmission scheme which can be employed when an eavesdropper is located near a receiver and channels are correlated. When the receiver-eavesdropper distance is short, it is difficult to obtain a security gain because the eavesdropper can have a similar channel compared to the receiver. To mitigate this problem, the receiver may transmit a jamming signal to prevent data acquisition from the eavesdropper. On this occasion to lessen the outgoing interference caused by the jamming signal to external communication networks, we assume that the sum of the transmission power of the transmitter and the jamming power of the receiver is kept constant. Under this restricted power consumption condition, we evaluate the security performance of our proposed transmission scheme using two metrics, such as threshold outage probability and secrecy capacity. By simulation, we find the optimal power consumption ratio between transmission power and jamming power which maximizes the threshold outage probability. We also analyze the secrecy capacity by simulation and numerical results.