An efficient analysis method of the electromagnetic emissions in the frequency domain

This paper presents an efficient analysis method of the electromagnetic emissions. When the electromagnetic emission from the cryptographic module is measured at a distance, the electromagnetic emissions from other modules interfere to the target emission as noise. Under this condition the time and the number of data necessary for the analysis increase. In order to solve this problem we focus on measuring data in the time domain limited around the interesting point. Furthermore the data is analyzed after converting from time domain to frequency domain. The proposal method is examined through experiments.