Get Ready, North Korea: The Army Wants Deflector Shields Against EMP Blasts
Which nation is most likely to emerge victorious from a war where electromagnetic pulse weapons are used? The nation that has the most effective EMP weapons, or the nation with the best anti-EMP defenses?
EMP seems poised to become a feature of twenty-first century warfare. The U.S. government fears that a North Korean ICBM could devastate America's electronics infrastructure with a nuclear EMP blast. At the same time, Russia is developing conventional missiles and ground-based emitters whose electromagnetic blasts could fry computers and electronic gear. And not to be outdone, the United States is considering cruise missiles that would fire bursts of microwave energy that would knock out those North Korean ICBMs before they hit America.
It's not that the EMP danger is new. The residual effects of nuclear weapons have been known since Hiroshima. But in the 1950s, EMP might have just disabled some radios and big mainframe computers. Today, many if not most munitions have some kind of electronic component.
So it's no surprise that the Pentagon wants to harden its weapons against electromagnetic blast. A U.S. Army research project is looking for ways to shield munitions against EMP and also electromagnetic interference, or EMI (when electronic devices interfere with each other). “Shielding of electrical and electronic devices and systems from catastrophic effects of high levels of EMI and EMP radiation presents an ongoing challenge,” the Army says. “This problem is exacerbated by the wide range of EMP devices ranging from hand-held, operating from battery packs to much larger systems capable of rendering havoc over many city blocks.”
The problem now is that “currently used EMI and EMP shields are effective for the protection of electrical components under small levels of such electromagnetic illumination.” In addition, the electromagnetic blast can travel over multiple frequencies. Current defenses focus on electromagnetic radiation seeping through access ports or wires connecting to the outside. The Army sees possible solutions as including the use of meta-materials, or composite material with nano-structures that minimize transmission through a combination of scattering, guiding and absorption.
Interestingly, technology that can protect weapons from EMP can also protect people and their personal gear. “Such solutions may also be extensible to wearable EMI and EMP shields for protection of military personnel and weapon platforms,” the Army notes.
These don't exactly sound like the deflector shields of Star Trek, or the personal force fields in the Dune science fiction novels, which repel objects traveling at high speed (and which provide a convenient plot device for the characters to battle with swords instead of guns). But this does suggest a future where soldiers—and civilians—will wear protection against electromagnetic blast.