Use of Electro-Magnetic Analysis to monitor activity of a digital circuit in a non-intrusive way

In this paper we introduce a fully non intrusive test method which is based on the Differential Electro-Magnetic Analysis (EMA). Our objective is to demonstrate the capability of this new method to detect a modification in a circuit, like a fault voluntary injected would be. This detection is carried out by comparing a reference trace, called Reference Signature, with a differential trace representing the observed electro-magnetic activity, called Control Signature. The results show the efficiency of the proposed method. We will then introduce the possibility offered by EM measurement to be used to detect a degradation of physical parameters on Avionics equipments where no intrusion is allowed.