A forensic detection system for intentional electromagnetic interference (IEMI) attempts

Regular operation of electronic devices can be disrupted by excess energy being introduced into the system, be it by signals travelling on cabling or freely propagating electromagnetic waves of high power. Since ensuing error patterns like system crashes are hard to trace back to their root cause, a detection system raising awareness of unusually strong field strength environments being present at critical facilities can inform effective mitigation measures. Our self-designed laboratory demonstrator can measure disruption signals of up to many kilovolts per meter, correcting for the frequency response of all components in case of narrowband signals based on frequency measurements down to a few megahertz accuracy when averaging over pulses. Additional acquired meta data like the signal envelopes with down to 10 ns time resolution and other measured pulse train charateristics allow for signal forensics. A four-channel design enables direction detection of the incoming signals. The cubic detector of 19 cm edge length can run on battery for 10 hours, a fibre-optic network connection allowing browser access to its web interface.