This paper introduces a procedural method based on fuzzy logic to analyze systematic the risk of an electronic system in an intentional electromagnetic environment (IEME). The method analyzes the susceptibility of a complex electronic installation with respect to intentional electromagnetic interference (IEMI). It combines the advantages of well-known techniques as fault tree analysis (FTA), electromagnetic topology (EMT) and Bayesian networks (BN) and extends the techniques with an approach to handle uncertainty. This approach uses fuzzy sets, membership functions and fuzzy logic to handle the uncertainty with probability functions and linguistic terms. The linguistic terms add to the risk analysis the knowledge from experts of the investigated system or environment.

Intentional electromagnetic interferences (IEMI) are able to disturb
susceptible electronic systems

There are different methods that are usually applied in the risk analysis,
e.g. the electromagnetic topology (EMT) (

An example for operation on Fuzzy Sets

Fuzzy-Logic operator: disjunction, conjunction and complement.

Based on the introduced theoretical approach published in

The fuzzy approach (

The fuzzy set

As in the classical set theory, fuzzy sets have their own mathematical
operators such as union, intersection and complement (Fig.

Instead to the classical set theory, the mathematical operation on fuzzy sets
are based on the membership functions. The operation for classical sets are
shown in Fig.

Mapping of the availability on the probability of occurrence

To predict the risk at system level of a complex electronic installation
(example the complete IT-System of a critical infrastructure) it is necessary
to characterize the behavior of each subsystem. Furthermore, it is important
to characterize the environment of the investigated infrastructure with their
buildings and surrounding areas. In the paper of (

To predict the risk level for the system with the consideration of its
environment, a map of accessibility zones and needed mobility
(

This information of the IEMI scenario are not enough to predict the risk.
Non-physical data are added with linguistic terms. This data can be the
accessibility to the infrastructure, the mobility of a source, the
availability of a source and any other experts opinion to improve the
prediction of the risk level (

A compound of different microcontroller circuits is used as the victim system
in determination of breakdown failure levels and is illustrated in Fig.

For one minute the system is exposed by 200, 500, 1000, 2000 or 5000 pulses
at different positions in the GTEM-cell. The different positions lead to a
different electric field magnitude. The results of the malfunction of the 300
repetition and a field amplitude of 20 kV m

The prediction of the risk level for the victim system includes the breakdown
behavior of the microcontroller compound (Fig.

An example to estimate the hazard level as a function of the mobility, the
scale of accessibility challenge, the likelihood of occurrence and the
detection level for IEMI sources is shown in Fig.

The results of the technology challenge, mobility-, threat- and hazard level
of the fuzzy systems lead to a probability of occurrence and a possible field
strength. Both results are mapped on the risk level membership function
(Fig.

The obtained results have to integrate onto the area plan (Fig.

We show the usage of the theoretical approach published in

The results shown in this paper were partly produced with the support of the Bundeswehr Research Institute for Protective Technologies, NBC-Protection in Münster, Germany (E/E590/CF149).

We acknowledge support by Deutsche Forschungsgemeinschaft and Open Access Publishing Fund of Leibniz Universität Hannover. Also, the results shown in this paper were partly produced with the support of the Bundeswehr Research Institute for Protective Technologies, NBC-Protection in Münster, Germany (E/E590/CF149).The publication of this article was funded by the open-access fund of Leibniz Universität Hannover. Edited by: F. Gronwald Reviewed by: two anonymous referees