Physical Layer Security Research Based On Nonzero-sum Game Theory In Wireless Communication

Wireless communication is the important part in the modern communication and has a wide application. Due to the broadcast nature of wireless channels, the issues of privacy and security have taken on an increasingly important role in wireless network. Cooperation between wireless network nodes is an efficient technique for improving physical(PHY) layer security of wireless transmission, in the presence of eavesdropper. However, the secrecy performance would be badly influenced by untrusted relay(UR) who do not cooperate completely. The untrusted relay may act as selfish node or even malicious node. A promising solution to solve this problem is to predict the behaviors of the UR in advance. Then, appropriate defense strategy can be obtained.In this paper, we consider a multi-relays network which include of untrusted relays, eavesdropper, source and destination in the network. Secure communication is achieved via nodes cooperation in AF scheme. It also takes relay weight ? and harmful factor ? into account. A nonzero-sum stochastic game is established to capture the interaction among the UR behaviors and the detection system strategies. Secrecy capacity is investigated as game payoff parameter to indicate the untrusted behaviors of the relays. Finally, we propose an algorithm to obtain the maximum probabilities of the behaviors of relay and the optimal system detection strategy.