LED显示系统的视频信息泄漏研究

发布时间：2018-06-10 04:41

本文选题：LED显示系统 + 信息泄漏　；参考：《西安电子科技大学》2014年硕士论文

【摘要】：近年来,随着信息技术和计算机技术的不断发展,LED大屏幕因其优良的显示性能而得到了广泛关注,已被应用于越来越多的场合。但此系统高速的工作频率,脉冲大电流驱动,数量极大的导线、接插件和高频开关电源,外壳因显示而无法完全屏蔽等诸多因素,都使得LED大屏幕显示系统的电磁辐射相当严重,不可避免地存在视频信息泄漏的风险。对LED大屏幕显示系统的视频信息进行电磁泄漏检测与防护技术研究,是我们所面临的新课题。本文以基于FPGA控制和以太网传输的LED显示系统为研究对象,在了解其组成结构与工作原理的基础上,根据研究的方向性与必要性对整个系统进行了模块划分,并对各模块潜在的视频信息泄漏源进行了初步定位。之后,对LED视频源、LED发送/接收系统以及LED扫描驱动系统三个模块的功能特性、工作原理、信号处理过程及线缆传输方式等展开了细致的理论研究,建立信号模型并仿真得到直观的时、频域特征。最后结合各潜在泄漏部位的实际测试结果,验证了建模方法的正确性,也分析判断出各关键电路是否存在视频信息泄漏问题,得到相关结论。电磁能量的传输方式有辐射性耦合和传导性耦合两种。前述的分析及结论都为该系统的电磁泄漏抑制方法研究提供了理论基础。对于主机、控制器、LED屏体等设备存在的辐射性耦合,可采用基于完善的屏蔽技术的工程加固方案。包括设备的电源线、USB控制线和各模块间不同的视频传输线缆在内,线上的传导耦合对信息泄漏的判断有很大影响,也可能作为新的辐射源再次对信息安全构成威胁。抑制传导干扰最为有效的手段则是EMI滤波器。文章对EMI滤波器的传输网络、关键参数及设计方法进行了分析与探讨,最终设计并制作了EMI电源滤波器,通过仿真与测试对其性能做出综合评估,论证了此抑制器件的可行性与有效性,具有很好的工程应用价值。
[Abstract]:In recent years, with the continuous development of information technology and computer technology, LED large screen has been widely concerned because of its excellent display performance, and has been used in more and more occasions. However, the system has many factors, such as high working frequency, high pulse current drive, a large number of wires, connectors and high frequency switching power supply, and the shell can not be completely shielded because of display, etc. The electromagnetic radiation of LED large screen display system is very serious, which inevitably leads to the risk of video information leakage. It is a new task for us to study electromagnetic leakage detection and protection technology for video information of LED large screen display system. In this paper, the LED display system based on FPGA control and Ethernet transmission is taken as the research object. On the basis of understanding its composition and working principle, the whole system is divided into modules according to the direction and necessity of the research. At the same time, the potential video information leakage source of each module is preliminarily located. After that, the function characteristics, working principle, signal processing process and cable transmission mode of LED video source LED sending / receiving system and LED scanning drive system are studied in detail. The signal model is established and the visual time and frequency domain features are obtained by simulation. Finally, the correctness of the modeling method is verified by combining the actual test results of the potential leakage sites, and the problem of video information leakage in every key circuit is analyzed and judged, and the relevant conclusions are obtained. There are two modes of electromagnetic energy transmission: radiative coupling and conductive coupling. The above analysis and conclusions provide a theoretical basis for the study of electromagnetic leakage suppression method of the system. For the main engine, the radiation coupling of the LED screen and other devices can be adopted based on the perfect shielding technology. Including the USB control line of the equipment and the different video transmission cable among the modules, the conduction coupling on the line has a great influence on the judgment of information leakage, and may pose a threat to the information security again as a new emitter. EMI filter is the most effective method to suppress conduction interference. In this paper, the transmission network, key parameters and design methods of EMI filter are analyzed and discussed. Finally, the EMI power filter is designed and manufactured, and its performance is evaluated by simulation and test. The feasibility and effectiveness of the device are demonstrated, and it has good engineering application value.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN873

【共引文献】