Research On Physical Layer Security Of Energy-harvesting-based Cooperative Communication Network

With the rapid growth of wireless data services,wireless communication services,especially for 5G networks and sensor networks,are facing the choke point of increasing energy consumption,energy-harvesting-based cooperative communication network(For the convenience of description,it is abbreviated as energy-harvesting cooperative network)has become a new research hotspot.In energy-harvesting cooperative network,wireless devices with limited energy harvest energy from radio frequency signals for information processing and transmission.At the same time,through the cooperation between users,it improves the communication quality of blind spot area and cell edge users,improves information transmission rate and energy utilization efficiency,increases the endurance of mobile nodes,thus prolongs the network life time.Due to the openness of energy transmission,there are security defects in the energy-harvesting cooperative network,while the constraint of nodes energy consumption makes it not suitable for complex high-layer encryption.In view of the above background,this dissertation studies the physical layer security performance of energy-harvesting-based cooperative communication network.In the energy-harvesting cooperative network studied in this dissertation,the legitimate source node communicates with the destination node through the relay node,and the relay node harvests the energy in the source node signal for information processing and forwarding.When there are illegal eavesdropping users eavesdropping on the confidential information sent by the legitimate node,the system may have the risk of information disclosure.In order to improve the security performance of the system,this dissertation uses cooperative jamming schemes to weaken the eavesdropping ability of eavesdropping node by sending noise signals from intermediate node or destination node.Firstly,for the energy-harvesting cooperative network with eavesdropping node,schemes of slot allocation and energy-harvesting are proposed,and the secrecy outage probability under the network model is theoretically derived and analyzed.Then,the existing network model is improved,the intermediate node equipped with energy-harvesting is introduced to interfere with the eavesdropping node by sending noise signal,and the analytical expression of the secrecy outage probability under this scheme is derived theoretically.Finally,the simulation software is used to compare the security performance of the energy-harvesting cooperative network under the cooperative jamming scheme of the intermediate node and the scheme without cooperative jamming,and the influence of different factors on the system security performance is analyzed.The results show that the security performance of the existing network model is poor,and the cooperative jamming scheme of intermediate node helps weaken the eavesdropping ability of eavesdropping node and improve the physical layer security performance of the system.Secondly,considering the impact of increasing the complexity of the system brought by the intermediate node,a cooperative jamming scheme of the destination node is proposed.In the Research scenario of energy-harvesting cooperative network,in order to improve the security performance of the physical layer of the system,the schemes of the destination node transmitting the noise signal to interfere with the eavesdropping node in first hop or second hop of the confidential information transmission is proposed.Then,the analytical expressions of system secrecy outage probability under the two schemes are derived,the security performance of the system under the cooperative jamming scheme of the destination node and the scheme without cooperative jamming is simulated and compared,and the influence of different factors on the system security performance is analyzed.The results show that the destination node cooperative jamming scheme helps improve the physical layer security performance of energy-harvesting-based cooperative communication network.