Method For Detecting Electromagnetic Information Leakage From Computer Monitor

The computer monitors can generate electromagnetic (EM) information leakage, which is related to the display principle. Refresh rate, horizontal frequency, and pixel frequency were confirmed as key factors to reproduce video images showed on the monitor from EM radiation. To estimate the risk of information leakage, a detection method based on the display principle was introduced. The method is to distinguish and match the spectrum interval from the radiated EM signals by multi-resolution spectrum analysis. Using the proposed method, EM information leakage such as working frequencies of the computer monitor was effectively identified.