显示器电磁泄漏信息的接收和重视

计算机电磁泄漏信息的接收和重现对信息侦收和安全传输都具有重要意义。显示器上的信息是有用信息的最直接体现，而且很容易通过电磁辐射产生泄漏。通过无线接收显示器的电磁辐射信息并经过数据采集卡输入到计算机，实现了原始信息的还原处理，该系统适用面广，方便灵活，运行结果证明该方法是切实可行的。     

小波分析用于显示器电磁泄漏信息的重现

计算机电磁信息泄漏是信息安全的一个隐患。文章设计了无线接收计算机设备电磁辐射信号的系统，针对泄漏信息中包含复杂干扰信号的问题，利用小波分析对接收到的显示器电磁泄漏信息进行滤波和除噪处理。实验结果证明：小波能够很好的改善还原效果。     

计算机液晶显示器电磁信息泄漏隐患分析

针对传统计算机干扰器能否适用于目前已普遍使用的液晶显示器这一问题,通过分析CRT显示器与液晶显示器工作原理的异同,以及计算机电磁泄漏与接收原理,认为尽管液晶显示器面板本身产生电磁信息泄漏的可能性较小,但其视频预处理电路及模拟信号接口存在电磁信息泄漏的可能性,并且正确使用现有计算机干扰器可有效防止液晶显示器电磁信息泄漏.     

计算机电磁信息泄漏阈值效应研究

基于进场实测数据,建立了计算机视频信号的电磁辐射模型,利用计算电磁学的方法定量地研究了计算机视频信号的电磁辐射强度;提出了信息泄漏阈值和信息识别度的概念,进一步研究了信息泄漏阈值与信息识别度的关系以及信息识别度与接收距离的关系;定量地研究了电磁泄漏信息截获与再现的关键因素和条件。     

计算机电磁辐射信息识别特性研究

基于实测数据,建立了计算机视频信号的电磁辐射模型,利用计算电磁学的方法定量地研究了计算机视频信号的电磁辐射强度;提出了信息泄漏阈值和信息识别度的概念,研究了视频电磁泄漏信息在不同信息泄漏阈值及信息识别度情况下的时域和频域特性,进一步研究了信息泄漏阈值、信息识别度以及接收距离之间的关系;定量地分析了电磁信息泄漏截获与再现的关键因素和条件.     

基于视觉效应的视频信息电磁泄漏抑制方法研究

计算机的电磁辐射会包含视频信息从而造成的信息泄漏,本文在随机置乱的基础上,根据人眼视觉效应提出了互补置乱的方法来抑制视频信息通过电磁辐射的泄漏.通过对相邻的每帧视频信息进行加减随机噪声,使得人眼视觉观察效果抵消掉噪声对视频图像的干扰,在叠加噪声的同时,保证了视频图像的清晰度,同样也达到了抑制视频信息电磁泄漏的功能.最后也通过实际截获实验,验证了该方法的可行性.     

VDU视频信息电磁泄漏侦收系统的研究

计算机显示器(visual display unit-VDU)是电磁发射源,这种电磁发射会导致视频信息泄漏.文章提出一种用于侦收VDU视频信息的模拟-数字综合系统,分析了VDU电磁发射的接收和视频信息的重建,给出了实验测试结栗和信号重建实例,说明该系统可有效应用于对计算机系统的信息攻击.     

计算机视频电磁信息泄漏效应研究

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。     

计算机电磁泄漏信息的接收与重现

研究了计算机电磁泄漏信息的检测、接收与重现技术。分析了计算机辐射发射的频谱特征,探讨了计算机发射电磁波的接收原理、方法,实现了计算机电磁泄漏信息的无线接收、再现。促进实现计算机信息安全防护与电磁兼容性设计。     

阴极射线管(CRT)显示器信息电磁泄漏频谱分析方法

CRT显示器偏转系统和电子束的电磁辐射会导致信息泄漏。本文提出一种分析CRT显示器信息电磁泄漏频域特性的方法：从信息攻击所处的场点出发，先将产生辐射的电流变换到场点时域波形，然后利用Welch平均周期图法分析辐射信号的功率谱密度。文章同时给出了更精确的模型近似电子束电流，文中理论计算结果和实验测试结果吻合。     

信息时代电磁兼容领域的挑战与应对(特邀文章)

论述了信息时代电磁兼容领域的挑战与应对策略.提出了信息社会安全的基础是网络与设备的电磁信息安全的理念；提出了电子设备不经意电磁发射引起的电磁信息漏泄的原理模型.分析了无处不在的电磁发射信息安全问题，综述了TEMPEST计算机研究的现状和发展趋势，论述了现代机器人、有线网络、无线网络以及工业网络的电磁信息安全问题.最后，展望了发展中的安全电磁兼容标准，阐述了现代工业和控制系统正在面临的越来越严重的信息攻击已经成为威胁国家关键基础设施的"超级武器"的国际动态.     

计算机线缆的电磁信息泄漏智能分析方法

计算机系统中的各型线缆会通过电磁传导发射泄漏内部信息,导致信息安全问题. 为了分析来自计算机线缆的电磁信息泄漏,提出了基于深度学习的智能分析方法. 设计一维卷积神经网络算法,对电磁泄漏信号进行深层的特征提取与学习,从泄漏的电磁信号中智能识别泄漏源的线缆类型,进而分析其中泄漏的视频信息. 实测结果表明,本文提出的方法,在未知目标信号特征的情况下,能够有效识别电磁信息的泄漏源与泄漏信息,为计算机线缆提供了一种电磁信息泄漏的智能分析手段.     

An electromagnetic interaction modeling advisor

A knowledge-based approach for the modeling of electromagnetic (EM) interactions in a system is described. The purpose is to determine any unwanted EM effects that could jeopardize the safety and operation of the system. Modeling the interactions in a system requires the examination of the compounded and propagated effects of the EM fields. A useful EM modeling approach is one that is incremental and constraint-based. The approach taken here subdivides the modeling task into two parts: (a) the definition of the related EM topology and (b) the propagation of the EM constraints. A prototype of some of the EM constraints has been implemented in Quintus Prolog under NeWS on a Sun workstation. User interaction is through a topology drawing tool and a stack-based attribute interface similar to the HyperCard interface of the Apple Macintosh computer     

Electromagnetic radiation from selected telecommunications systems

Because of the growing interest in potential health effects associated with exposure to electromagnetic (EM) radiation at microwave and radio frequencies (RF's), a study was initiated within the Bell System to document existing levels of EM energy associated with various radio transmission systems. To this end, power density and electric field strength measurements were made at selected facilities, particularly at locations judged to be representative of those frequently encountered by various crafts personnel. For the case of point-to-point microwave radio, measurements were made in the vicinity of various antenna towers in order to obtain information that could be compared with the corresponding levels predicted by analytical techniques. These data allow one to assess the environmental impact, with respect to EM radiation, of the microwave radio system as well as the impact of future standards and guidelines on the system. This paper describes the instrumentation and measurement techniques used for this study and provides a summary of the results obtained for several different types of radio systems including high frequency (HF) radio, tropospheric scatter, earth-satellite and ubiquitous microwave radio relay.     

并行UTD算法及在机载天线分析中的应用

要实现对复杂环境的EMC分析,最大的障碍是计算量过大,耗时太长.本文提出MPI结合UTD的并行算法,实现了大型复杂飞行器机载天线的方向图特性分析.数值结果表明,并行UTD算法可以大大节省计算时间.这一方法为在小型机系统下实现大型EMC分析软件提供了坚实的基础.     

1千伏以下的金属球间隙静电放电辐射特性的测量研究

In this study, the characteristics of Electromagnetic (EM) radiation caused by Electrostatic Discharges (ESDs) from metal spheres charged to voltages less than 1 kV are examined experimentally. Our experimental system consists of a pair of spherical elec-trodes of different diameters, a 1-18 GHz-band- width horn antenna and a 20-GHz-bandwidth digitizing oscilloscope. Polarization, waveform duration and peaks of antenna-received voltages from the EM field radiation are measured in order to clarify the EM radiation mechanism. The ratio of the received voltages between the antenna arr-angements of the field polarization parallel and perpendicular to the spark pass is 18 to 20 dB. The polarities of the antenna-received voltages are the same as those of the charge voltages across the gap. Moreover, the waveform duration and the first peaks increase with an increase in the diameters of the spherical electrodes. Consequently, we find that the polarization, waveform duration and first peaks of the EM field radiation can be explained by a dipole antenna structure, which makes the spark part of the spherical electrodes a feeding point on the straight line passing through the centres of the two spheres.     

基于GPRS的电梯在线监控系统的设计

由于信号在CAN总线中有效传输距离有限,为此对采用CAN总线技术的电梯远程监控系统,提出了一种基于嵌入式ARM处理器和GPRS无线通信技术的电梯远程监控系统的方案。通过由LPC2148和EM310组成的电梯终端将电梯的运行状况和故障信息经GPRS网络及时发送到远程监控中心,然后经由监控中心上位机软件的操作,实现了电梯的远程监控,解决了信号传输距离的问题。     

A Review of Numerical Models for Predicting the Energy Deposition and Resultant Thermal Response of Humans Exposed to Electromagnetic Fields

For humans exposed to electromagnetic (EM) radiation, the resulting thermophysiologic response is not well understood. Because it is unlikely that this information will be determined from quantitative experimentation, it is necessary to develop theoretical models which predict the resultant thermal response after exposure to EM fields. These calculations are difficult and involved because the human thermoregulatory system is very complex. In this paper, the important numerical models are reviewed and possibilities for future development are discussed.     

宠物管理系统中RFID读卡器设计

在宠物管理系统中RFID读卡器是用来读取动物标签信息的,并将信息传输给上位机。RFID读卡器系统主要是由EM4095基站芯片和ATmega88单片机构成的,EM4095基站芯片发射载波并接收、解调标签返回的数据波形。根据ATmega88单片机具有的捕获功能,提出一种结合ISO11784/11785协议进行Biphase软件解码的方法,获得标签的数据信息。读卡器结构简单、工作稳定,有很好的通用性。