A low-cost and efficient method of determining the best frequency band for video leaking signal reconstruction

Determining the best frequency band for reconstructing display video leaking signal is the key problem in TEMPEST, which is the technology of electromagnetic leaking research. To solve such problem, a novel algorithm based on spectral centroid has been developed. Using the property that spectral centroid can accurately identify the signal energy center in frequency domain, the proposed algorithm can find best frequency band automatically. The uniformity degree of spectral centroid spacing distribution is defined to find the best frequency band which has the highest signal to noise ratio (SNR). Thus the video leaking signal reconstruction can be realized efficiently without expensive equipment.