Research On Physical-layer Security Performance Based On Industrial Wireless Sensor Networks

Machines and devices need to transmit a large amount of information in the industrial wireless sensor networks.The security and reliability of communication systems have become more and more important.Because of the development,the modern computing ability has been constantly improved,it is possible to crack the encryption algorithm in this age.Physical-layer security can provide a new way to solve the problem.In this paper,we improved the the physical-layer security performance of the industrial wireless sensor networks by using the relay cooperation and artificial noise jamming.In traditional industrial wireless sensor networks always use the direct transmission or conventional round-robin.Using the relay cooperation can effectively deal with complex environments,channel fadings,long-distance transmission and eavesdropping.In this paper,we proposed the optimal relay secure transmission scheme in Nakagami fading channels.We derived the expressions of the outage probability and the intercept probability for the optimal relay transmission scheme based on amplify-and-forward(AF-BRS-E)and the optimal relay transmission scheme based on decode-and-forward(DF-BRS-E),and analyzed the relationship between the power,the numbers of relay and channel conditions.The simulation results showed that the two schemes can reduce the outage probability and the intercept probability effectively and improve the security of physical-layer.Comparing with AF-BRS-E scheme,DF-BRS-E scheme is more stable and less susceptible by channel environments.Adding artificial noise is also one of the important ways to improve the physical-layer security,which can suppress eavesdropping effectively,and improve the security and reliability of the physical-layer.In this paper,non-orthogonal multiple access technology(NOMA)is integrated into the traditional artificial noise jamming scheme,which can improve the security performance of physical-layer and save the spectrum resources.We Considered the untrusted relay nodes and proposed an artificial noise jamming scheme based on NOMA.We derived the expressions of the outage probability and the ergodic secrecy capacity,and the upper boundary expressions of the NOMA scheme has been gived.The simulation results showed that the NOMA scheme have lower the outage probability compared with the traditional orthogonal multiple access technology(OMA),and the ergodic secrecy capacity has been improved.It proved that NOMA scheme can improve the security and reliability of the physical-layer,and also prevent untrusted relay nodes to stealing information.