We consider a secure remote state estimation problem where the observations transmitted from the sensors to a remote estimator could be intercepted by an eavesdropper. To prevent the eavesdropper from acquiring the system states, we propose an encoding–decoding mechanism by combining linear transformation and artificial noise to ensure the exact values of observations unavailable to the eavesdropper but available to the estimator. Further, we propose an algorithm by which the eavesdropper may infer the approximate values of the observations and thus to further estimate the system states. We reveal how the amplitude of the artificial noise affects the accuracy of the eavesdropper inference, which helps the designing of the encoding–decoding mechanism. Simulation experiments are conducted to verify the derived results.

我们考虑一个安全的远程状态估计问题，其中从传感器传输到远程估计器的观测值可能被窃听者拦截。为了防止窃听者获取系统状态，我们提出了一种编码解码机制，将线性变换和人工噪声相结合，以确保窃听者无法获得但估算器可以使用的观测值的准确值。此外，我们提出了一种算法，通过该算法，窃听者可以推断观测值的近似值，从而进一步估计系统状态。我们揭示了人工噪声的幅度如何影响窃听者推断的准确性，这有助于编码/解码机制的设计。进行仿真实验以验证得出的结果。