Posts Tagged ‘emp’
Tapping Audio Signal Processing Tech, French Researchers Develop Long-Range ‘EMP Bazooka’
The work taps an audio signal processing technique (also invented by a French physicist in 2004) called time reversal signal processing. Using what's known as a time reversal mirror, researchers found they could take a short pulse of electromagnetic energy fired from one antenna and bounce the exact signal back with its wave-form perfectly reversed (hence "reversal mirror"). This relies on yet another device, a arbitrary waveform generator, which can generate pretty much any waveform in a matter of milliseconds.
This process allows the researchers to exploit another principle, known as the "pulse compression property" of time reversal, which generates a significantly amplified version of the signal at some point outside of the reverb chamber housing all the other gizmos. Set up in the proper array, the engineers were able to create an arrangement that could amplify the original signal by 10,000 times. Needless to say, that's enough to crank up a relatively weak EMP signal to devastating levels that could be used to disable electronic devices from a distance.
That could be a problem, of course, for militaries around the globe that rely on growing arsenals of electronic gear. There's also a security question; an EMP weapon placed with ill intent could disable an aircraft on approach or takeoff, or be used to throw economies or defensive systems into chaos by crippling key computer networks. Further, it doesn't appear that such a weapon would necessarily require highly technical know-how or hard-to-acquire hardware or materials. But on the bright side, such an EMP bazooka could prove quite effective in the upcoming war with the machines.
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Should I Be Worried About Electromagnetic Pulses Destroying My Electronics?
Despite the grid’s numerous built-in safeguards, if enough transformers go down, they could take large chunks of the grid with them. The only way to get it running again would be to replace all the damaged gear. CMEs aren’t usually disastrous, but the two largest blasts on record, which took place in 1859 and 1921, could each knock out the Northeast power grid if they happened today. On the bright side, although CMEs have been known to put satellites out of commission, our atmosphere deflects most of the energy, so the radiation is too diffuse by the time it reaches your electronics to destroy them.
A man-made EMP poses a greater threat. If one goes off in your neighborhood, there’s a significant risk that the concentrated pulse will induce extra voltage in the circuit-board components, frying them for good. The best bet for protecting your electronics is to store them in a Faraday cage: a cube of interweaving metals, preferably copper and quarter-inch-thick steel, which together can act as an electromagnetic shield. Like in a lightning rod, the copper attracts electricity while the steel absorbs magnetic pulses. A cage big enough to hold all your favorite gadgets—your cellphone, TV, computer, and so on—runs in the neighborhood of $15,000. An EMP could also crash the power grid, so you might want to spring for an extra cage to protect your generator too.
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