Power Allocation for Physical Layer Security Among Similar Channels

Physical layer security technologies are used to ensure the secure communication when eavesdroppers use infinite computing capabilities to launch brute force attacks. Traditional physical layer security technologies utilized the difference between legitimate channels and eavesdropping channels. However, in certain scenarios, the legitimate channels are similar to eavesdropping channels so that the communication become insecure. In this paper, we especially studied the physical layer security communication among similar channels. An interference relay model was proposed to ensure the security of communication and at the same time, optimize the power allocation by maximizing the lower bound of the secrecy outage probability. The theoretical secrecy outage probability of the proposed power allocation scheme was derived. Simulation results show that the proposed scheme is superior to a uniform power allocation scheme on channel security performance under the same condition. Furthermore, using simulation, we demonstrated that the derivation of secrecy outage probability for the proposed power allocation scheme is valid.