Eavesdropping the display image from conducted emission on network cable of a PC

The display image of a PC can be reconstructed by using the conducted emission on the PC＇s network cable. The relevant signals which be used to reconstruct the original image are coupling from the radiation of the switching of red, green, blue （RGB） signals in PC. These pertinent signals are partly contained in the frequency region higher than 30 MHz in the conducted emission. From these findings, the near-field coupling principle from PC to the network cable is analyzed firstly. And then, a multi-conductor transmission model for the RGB signals which transmit in the network cable is proposed. In addition, the maximum safe distance is estimated by using this model. In order to check the validity of the estimating distance, the eavesdropping experiment is carried out to reconstruct the original display image. The results demonstrate that the blurred display image can be retrieved at the place of 29.5 m.     

总裁声音

凡事不可能一蹴而就,总得花时间慢慢来。——谷歌CEO拉里·佩奇认为,创业者需要有耐性,决不能操之过急,要搞清自己到底想要一家什么样的公司。跟不上时代的步伐,谁就是下一个柯达。——联想集团董事长兼CEO杨元庆指出,当一个企业壮大之后,竞争对手会用更激进的方法与之竞争,这个企业就需要付出比以往更多的努力。预测未来的最好方式是创造未来。     

测试和测量

内置多端口无线通信测试仪E6607C EXT-C是一款整合式单机综合测试仪,其配置包括矢量信号分析仪、矢量信号发生器、高速序列分析仪和8个用于无线蜂窝制式的双向输入/输出端口,以及4个用于GNSS测试的输出端口。针对最新无线调制解调器芯片     

试听派扬HiFi—4书架式音箱

其实一直以来，中国本土的音响品牌。一直在Hi-Fi的道路上孜孜以求，不断进取，他们推出的音响产品做工精良、用料扎实、声音品质出色，最关键的是在价格上较进口知名品牌的产品要廉宜不少，成为众多追求性价比的工薪一族发烧友的上佳之选。     

Effective Action for Noncommutative U（1） Gauge Theory with Higher Dimensional Terms

In this paper we apply the assumption of our recent work in noncommutative scalar models to the noncommutative U（1） gauge theories. This assumption is that the noneommutative effects start to be visible continuously from a scale ANC and that below this scale the theory is a commutative one. Based on this assumption and using background field method and loop calculations, an effective action is derived for noncommutative U（1） gauge theory. It will be shown that the corresponding low energy effective theory is asymptotically free and that under this condition the noncommutative quadratic IR divergences will not appear. The effective theory contains higher dimensional terms, which become more important at high energies. These terms predict an elastic photon-photon scattering due to the noncommutativity of space. The coefficients of these higher dimensional terms also satisfy a positivity constraint indicating that in this theory the related diseases of superluminal signal propagating and bad analytic properties of S-matrix do not exist. In the last section, we will apply our method to the noncommutative extra dimension theories.     

一句话新闻

派睿电子携手FCI推进本土连接器市场发展；安森美半与TCL设立联合电源实验室；北京东微推出32通道微弱电流信号放大集成电路；     

600MHz带宽示波器

R＆SRTO系列最新推出适用于低带宽领域的600M带宽的示波器，该示波器既能满足客户对复杂信号进行深度分析又能满足低带宽的要求。R＆SRTO示波器采用数字触发系统，     

环绕声究竟离我们有多远？

大自然的声音从来就是包围着我们人类的。当然大自然发出的声音也没有单声道的，但是如果某个人的双耳有一只失去昕觉，那么此人感受的世界就是单声道（亦称单耳声）的了，如果两只耳朵都不能听的话。那么对于他来说，这个世界是没有声音的。所以，所谓单声道、立体声和环绕声是对有两只耳朵及其听觉系统的人类而言的。