Event-triggered H? Filtering Over Discrete Networked Systems Under DoS Jamming Attacks

With the renewal and iteration of science and technology,theoretical innovation,algorithm innovation,and practical innovation are constantly breaking through the original technical bottlenecks.Under the technical background of multidisciplinary integration in network communication,cyber-physical systems(CPS)have also been rapidly developed and expanded.In control theory,the CPS system is usually described as a discrete state for analysis.For the network security of the system,risks can be avoided from the type and source of network attacks,and the performance of the system can be improved from the two perspectives of reducing channel delay and removing data redundancy.Overall optimization,based on the above analysis,this topic has been studied from three aspects:attack type,channel delay,and data redundancy.For attack types,there are regular attacks and disordered attacks.This article starts with regular attacks under special circumstances,namely periodic network attacks,and studies the linear discrete system triggered by events under periodic denial of service(DoS)interference attacks.H? Filter design method.Define the filter input signal according to the special attributes of the network attack.At the same time,considering the delay and packet loss properties in the sensor and sampler,combined with the event trigger mechanism to effectively reduce the channel redundancy and improve the overall performance of the system.Based on the above three points,the mathematical model of the switching system of the discretization filter is constructed,and the stability and H?performance stability conditions of the switching system are obtained by the method of Lyapunov-Krasovskii energy functional and free weight matrix.Regarding the disordered attacks in the normal state of the attack types,this article starts with the general disorder attack,that is,the aperiodic network attack problem,and studies the linear dispersion based on the event trigger under the aperiodic denial of service(DoS)interference attack.The H? filter design method of the system.According to the period and frequency of the disorder attack,the input signal of the filter is redesigned.At the same time,when the system encounters non-periodic attacks,in order to reduce channel useless data transmission,a new event trigger mechanism is introduced to optimize system performance based on the attack period and frequency relationship.After that,the mathematical model of the switching system of the discretization filter is established,and the system stability and H? performance stability conditions are obtained by using the piecewise Lyapunov-Krasovskii functional.According to the derived linear matrix inequalities(LMIs),the stability of the filter error system and the energy attenuation rate under DoS attacks in discrete systems are obtained.For large cyber-physical systems,even if the previous data is continuously iterated and optimized to remove duplication,it still has to bear a serious data load in the transmission channel link.High-speed,large-capacity,and narrow-bandwidth digital signals are stacked on the receiving and transmitting ends of various logic devices,greatly reducing the occupancy rate and transmission rate of data signals.Aiming at the common problems in such large-scale projects,this paper designs the quantizer and filter at the same time,which can not only reduce the communication cost in the network,reduce the transmission pressure of the channel,but also offset the influence of network disorder attacks.According to the attack period and frequency relationship,a new event trigger mechanism is introduced,and then the big data is passed to the digital quantizer to further optimize the system performance.According to the above method,the mathematical model of the switching system of the discretization filter is established,and the system stability and H? performance stability conditions are obtained by using the piecewise Lyapunov-Krasovskii functional of the time delay information.The linear matrix inequality is used to verify the stability of the filter error system and the energy attenuation rate of the discrete system with time-delay links under DoS attack.Finally,the feasibility and effectiveness of the proposed design method are verified by numerical simulation.