重放攻击下不确定CPS的安全滤波

Security-guaranteed Filtering of Uncertain Cyber Physical System Against Replay Attacks

主要研究重放攻击情形下离散不确定信息物理系统(CPS)的安全滤波问题。首先,为应对受限的通信资源,采用事件触发机制提高网络资源的有效利用率;其次,引入伯努利随机变量描述随机发生在传感器到滤波器之间的重放攻击,并构建攻击补偿项降低攻击对滤波性能的影响;接着,考虑不确定性、随机扰动以及重放攻击对系统的影响,给出滤波器安全性能指标;然后,借助线性矩阵不等式技术和随机分析方法,推导出滤波误差系统满足所提安全性能的两个充分条件;最后,通过一个数值例子验证滤波器设计方法的有效性。

The security-guaranteed filtering problem is studied for discrete-time uncertain cyber physical system(CPS)against replay attacks.Firstly,to deal with the limited communication resources,an event-triggered mechanism is adopted to improve the effective utilization of network resources.Secondly,the replay attacks that occur between the sensor and filter are modeled by the Bernoulli processes,and an attack compensation term is developed to mitigate the impact of replay attacks on filtering performance.Then,considering the effects of uncertainties,random disturbance,and replay attacks on the system,the safety performance index of the filter is proposed.Furthermore,based on linear matrix inequality technique and stochastic analysis method,two sufficient conditions are derived to ensure that the filtering error system meets the expected level of safety.Finally,the effectiveness of the proposed filter design method is demonstrated by a numerical example.