计算机视频电磁信息泄漏效应研究

The study on video electromagnetic information leakage of computer

基于计算机电磁辐射的实测结果,对计算机视频信号的电磁辐射机理进行建模,利用计算电磁学的方法计算了计算机视频信号的远场电磁辐射;提出了利用FDTD (时域有限差分) 计算电磁辐射伴随的噪声衰落的方法,表述了随机噪声的时变和远场特性;最后针对具有20dB噪声的泄漏电磁波进行软件模拟处理,利用同步、滤波、锁相、识别和重构等技术获得了再现的文字图像,研究了电磁信息泄漏现象,讨论了有关的规律。

The video signal electromagnetic radiation model is set up based on near-field testing data of computer electromagnetic radiation, and the far-field video electromagnetic radiation is computed using computational electromagnetics method. Further more, the idea to investigate noise propagation that are accompanying with electromagnetic radiation using FDTD method is proposed, and the characteristics of time variant and far-field are elaborated. Then, the electromagnetic radiation with 20dB noise is simulated. At last, the recovered word images are given after the video electromagnetic information leakage is processed with synchronization, correlated filtering, phase lock on, identification and reconstruction technology etc. The characteristics of information leakage is studied and discussed.