Compensation Control For Jamming Attacks In Wireless Control System

Industrial Wireless sensor networks(IWSN)is a multi-hop self-organization network composing of many inexpensive and small sensor nodes,which has broad application prospects in the industrial fields.The introducing of IWSN in the Wireless Control System(WCS)can make the system more flexible and expandable.However,due to the broadcastability of the information transmitted by the IWSN nodes,it is vulnerable to external environmental interference and human jamming attacks,which causes the increasing of packet loss rate and network delay in the WCS,and further causes system stability being impaired.In order to achieve secure and reliable transmission of network data,the compensation control for jamming attacks in wireless control systems is a key and difficult point to realize the safe operation of WCS.Based on this,this paper studies wireless control systems and industrial wireless sensor network technologies,starting from improving the security of wireless control systems and reducing the impact of jamming attacks on system stability.The strategies of delay compensation and packet loss compensation for jamming attacks in wireless control systems are studied.The following research works are carried out:(1)The jamming attack defense methods in industrial wireless sensor networks is studied.According to the shortest path of data packet transmission between the source node and the gateway node in the IWSN,the secure routing path is constructed by the path and the least packet loss principle.The routing mechanism of data transmission between IWSN nodes is studied.Based on the tracking feedback mechanism,the secure routing path with the least impact of the jamming attack is constructed,which is used to transmit the data sent by the controller and the sensor nodes,and reduce the impact of the jamming attack on the information transmission.(2)The packet loss compensation in the wireless control system is studied.On the basis of attack defense,for the problem of packet loss in the network caused by jamming attacks and interference noise in the wireless control system,the Kalman filter and the packet loss compensation security control strategy are adopted to perform packet loss compensation control on the packet loss in the forward channel and the reverse channel of the wireless control system,which will ensure the stability performance of the wireless control system under condition of jamming attacks and interference noise.(3)The delay compensation in the wireless control system is studied.Aiming at the reducing the control performance of wireless control system caused by the increasing of network delay due to jamming attacks in wireless control systems,the network delay prediction based on hidden Markov model and the network delay compensation scheme based on Smith predictor are adopted.The network state in the presence of jamming attack is modeled as a Markov model.The parameters of the HMM are trained by the observing of the network delay sequence,and the network delay is estimated by the Viterbi algorithm.Finally,the delay is compensated by the Smith predictor.OPNET and Simulink/TrueTime are used as joint simulation tools to verify the effectiveness of the research algorithm.The simulation results show that: 1)The secure path of the IWSN communication data route constructed based on the tracking feedback mechanism can well avoid the jamming attack node and reduce the network delay and packet loss rate in the network.2)The security control strategy of using Kalman filtering and packet loss compensation can greatly reduce the impact of interference noise and jamming attacks on system stability.3)The hidden Markov model can predict the state of the network under jamming attacks.The delay compensation based on the Smith predictor can meet the stability requirements of the system.