How to defend against EMP attacks

If you’ve ever watched The Matrix or Ocean’s Eleven, you’ll be familiar with EMP weapons — pulses of intense electromagnetic radiation that melt any nearby conductors, disabling just about any electrical system or electronic device. Despite their sci-fi-like portrayal by Hollywood, EMP weapons are very real, and very capable of destroying computers or knocking out a power grid. That’s why the Fraunhofer Institute in Germany has now created a device that can defend against EMP attacks.

While the Fraunhofer Institute device can’t actually defend against the crippling effects of an EMP weapon, it can detect the strength, frequency, and location of the attack. An EMP (electromagnetic pulse) is essentially just big, high-powered burst of radiation — and like other forms of radiation, such as a radio signal, it’s relatively easy to analyze that radiation to work out what exactly is going on.

The Fraunhofer instrument consists of four antennae on a tripod (facing different directions), a shielded box that houses some RF components (amplifiers, rectifiers, etc.), and a computer to analyze the resultant data. The Fraunhofer Institute rarely gives up more information than it has to, and sadly this case is no exception, so we have to do some guessing on how the instrument actually works. The antennae cover a quadrant of 90 degrees each, where they can detect “all types of electromagnetic sources.” In the shielded box there’s a “high-frequency module” that can determine when an electromagnetic pulse starts and stops. The computer then tallies this information up to work out where an EMP originated from, how long the EMP lasted, and what kind of EMP blast we’re talking about (weaponized, nuclear, non-nuclear, etc.) “Those affected by the attack can use this information to mount a rapid and appropriate protective response,” explains Michael Jöster from the Institute.

At this point, we should note that Fraunhofer’s device only works for small EMP attacks — non-nuclear EMPs that generally have very small, localized effects. The nuclear EMP that North Korea recently (reportedly) obtained from Russia is based on an atomic bomb, and would thus have enough energy to melt (fuse) every electrical system and electronic device for hundreds of miles — including the Fraunhofer Institute’s instrument. This new instrument would only be useful in defending against small, non-nuclear EMPs — and again, it would only help you locate the attacker after the EMP has already shut down your security system (or whatever else those terrorists are trying to shut down). If you’re the target of a nuclear EMP, there really isn’t anything you can do, short of shielding yourself with a lot of lead.

All of this leads me to ask an intriguing question: Just how common are these low-level EMP attacks? Fraunhofer says that at least one criminal group in Berlin has used suitcase-sized EMP devices to crack the security of limousines. Similar devices can be used to overcome alarm systems, though no real-world examples are given. In general, Fraunhofer says that consumer-grade devices (smartphones, cars) are most at risk from these suitcase EMPs — industrial systems usually have enough shielding that you’d need a serious EMP device to cause any damage. In general, there are very few reported cases of EMP attacks — but that isn’t to say they don’t exist. Presumably, if Fraunhofer has gone out of its way to mitigate against EMPs, there must’ve been demand from the Institute’s industry partners to develop such a device. Who knows: Maybe high-tech crime syndicates have suddenly started using EMPs — but in the interests of security and public relations, such attacks simply aren’t being publicized.