A Frequency-Integrated Electromagnetic Vulnerability Index for Electronic Systems in Complex Electromagnetic Environments

This paper proposes a frequency-integrated electromagnetic vulnerability index (FI-EVI), which is a reference-weighted susceptibility-screening metric for shielded electronic enclosures rather than a direct measure of functional failure. The frequency-resolved vulnerability is defined as the internal-to-reference RMS field ratio, VE(f) = Eint,rms(f)/Eref,rms(f), and FI-EVI is its log-frequency average from 10 MHz to 18 GHz. All cases use a swept-frequency incident plane wave of 1 V/m RMS and, as a common normalization benchmark, the MIL-STD-461G RS103 aircraft-internal limit (20 V/m up to 1 GHz and 60 V/m above). The internal field is obtained from an aperture-dominant reduced-order transfer function with parameters fixed in advance. A worst-case spectrum is derived under a fixed incident power-density budget and a peak power spectral density cap αSflat; the amplification factor is bounded by α. For three UAV-scale apertures (15, 60, and 150 mm), FI-EVI is 0.0056, 0.0094, and 0.0159, and the amplification factor at α = 10 is 1.27, 1.58, and 2.23. For one similitude-scaled family of a controlled loaded enclosure simulated with openEMS, the band-limited reduced-order FI-EVI is 9.4–21.5% below the full-wave envelope and within −11.0% to +7.3% of the maximum among the prescribed probe locations and polarizations, although the enclosure resonances are not reproduced.