Cognition Of Computer Video Information Interception Based On Virtual Instruments

The Modern society has entered the information era, and information has become critical resource supporting the normal functioning of the society, so information leakage has been widely concerned. Electronic information equipments or computers and their peripheral equipments will inevitably leak sensitive information accompanied with radiation. Without effective protection, it will bring a huge threat to personal privacy, social information security and even national security. Research on information monitoring and reduction technology in scattering electromagnetic waves environment, i.e.TEMPEST technology, has a very important practical and strategic significance.The thesis firstly introduces TEMPEST technology, and then analyzes the characteristics of the time domain and frequency domain feature of the leaked video information. Secondly the thesis describes the video leaked information intercepting platform based on LabVIEW. And at last the thesis expands the research. The main work and the new results are as follows:For extracting the sync signal and the center frequency in peak search process, two new solutions are proposed:one is to take advantage of the peak detection component of the LabVIEW platform coming with some manual control to complete the search of the peak; another uses smoothing preprocessing operator based on the triangular windows to operator the spectrum data.The Thesis designs a peak recognition algorithm to obtain peak information based on the method of least squares curve fitting design and verifies it by experiments. The experimental results show that both methods can improve the peak search accuracy, thereby increasing the quality of the resumption of video image.For real experimental scene, differences in antenna types, angles, distance will lead to large differences in intercepting the video signal. This thesis introduces the concept of electromagnetic database on variable measurement parameters, antenna bands and builds a database structures, which facilitates the analysis, comparison, management of the spectral data.