Fundamental Study on Restoration Method of Encoded Data from Electromagnetic Leakage Focusing on Error Detection Codes

In electromagnetic (EM) information leakage, conventional studies have focused primarily on unencoded information, which can often be partially restored despite losses. On the other hand, when targeting encoded data, even if there are errors of just a few bits, these errors can spread during decoding, making it difficult to restore the original information using conventional methods. To overcome these limitations, we propose a method that employs error detection codes— commonly included in transmission protocols for identifying noise interference—during the information restoration phase. This approach enables the complete and error-free restoration of data from leaked EM waves, even when dealing with encoded transmissions. Experimental validation demonstrates the efficacy of our method in fully restoring information from EM waves leaked from a webcam transmitting encoded signals.