A Study On Applied Technology Of Computer Video Leaking Information Interception

In this paper, the theory of interception technology on computer video-leaking information is discussed, several key techniques and practicable methods are described in detail. The proto type of an instrument designed by us for intercepting computer video-leaking information is introduced. The performance of this proto type is proved to be right with the results of large amount of test.At first, the meaning and its essentiality of interception technology on computer video-leaking information is explained. The growing history and general situation of this kind of interception technology are summarized, and the main work of this paper is pointed out.The second, the main work in the paper is discussed. They are include: the theory and character of electromagnetic leaking from a computer; the theory of accumulation mean filter and pectination filter; the analysis of synchronous signal precision, at 10-12 second level, for stably intercepting; the technology requirement of receiver and data acquisition board for clearly displaying the images recovered from the intercepted data. The third, after theoretically analyzing, the following practicable methods are put forward: 1) automatically pick-up the synchronous information by analyzing the spectrum of intercepted video-leaking information; 2) realizing the phase lock and the electronic image stabilization by integral-projection and differential-positioning; 3) improving the effect of accumulation mean filter and the pectination filter by using electronic image stabilization; 4) automatically adjusting image acquisition parameters by detecting the image entropy, therefore the quality acquired image is improved; 5) to realize the quantitative test of a leaking extent, a standard test picture was designed. Finally, a proto type for leaking information processing based on our techniques mentioned above and the virtual instrument principle was designed and tested.