[Infowarrior] - DARPA develops EMP countermeasures

[Richard Forno]

Original URL: http://www.theregister.co.uk/2008/08/28/darpa_pulse_weapon_countermeasure/

DARPA develops zap-bomb electropulse countermeasures
By Lewis Page
Published Thursday 28th August 2008 14:12 GMT

US military boffins are preparing highly sophisticated technical  
defences against the dreaded electromagnetic pulse bomb, a weapon  
which has long been anticipated but never successfully built.

We know about the counter-electropulse defence technology because the  
company which will develop it - HRL Labs of Malibu, California -  
announced their contract win yesterday. The programme is referred to  
by the Pentagon as Electromagnetic Pulse-tolerant Microwave Receiver  
Front-end, or EMPiRe*.

The idea of the attacking e-weapon is that it would release a hugely  
powerful radio-frequency or microwave pulse. In the same way that a  
normal, very weak emission is picked up by a radio or radar antenna to  
produce a measurable current, the weapons-grade pulse would induce a  
vicious surge in exposed electronic equipment - potentially frying it  
for good, or at least shutting it down for a bit.

Such weapons, it's often thought, might be driven by explosions or  
other rapid processes rather than normal batteries or generators,  
because of the need to release large amounts of power very fast: hence  
pulse bomb rather than pulse raygun etc.

Normally, the defence against this sort of thing is simple. You merely  
enclose your electronics in a conductive metallic Faraday cage,  
perhaps fashioned of trusty tinfoil if nothing better comes to hand.  
The problems of generating and focusing powerful electropulses are  
already enormous - so enormous, in fact, that decades of secretive US  
effort have failed to produce any working EMP weapons**. Producing an  
EMP which has range, focus and power sufficient to sizzle its way  
through a decent Faraday cage is just not on.

But there are problems here. Some kinds of electronics are no use if  
you wrap them up in a radio-proof box. In particular, a microwave  
receiver in a communications or radar set needs to pick up RF  
radiation - but if you let it, an EMP bomb or whatever might fry the  
electronics of the connected system.

HRL's proposed solution is to isolate the "front end" of the receiver,  
which will "sense incoming electrical fields through a high- 
performance microwave photonic link". The new HRL front end will pass  
information to the signal processors optically, meaning that no  
electric surge through into the protected back end is possible.

"The thermal effects of a high-energy attack will be insignificant  
because our sensor head absorbs negligible radio-frequency power,"  
says HRL Senior Scientist Dr James Schaffner.

HRL's research is funded by DARPA, the Pentagon's elite group of  
paradigm-punishing, technonoclastic nerd-wranglers. DARPA's goal often  
appears to the outsider to be that of rendering America's latest  
military tech obsolete well before it actually comes into service. In  
this case the Pentagon brainboxes may well excel themselves, as even  
the more ambitious ongoing US pulse-bomb efforts (http://www.theregister.co.uk/2008/01/18/terawatt_rf_hpm_emp_zap_blaster_weapon_hera/ 
) only see themselves starting a useful weapons programme from 2012.  
(To be fair, DARPA might be more worried about EMPs from nukes.)

Needless to say, some who already prefer to be on the safe side  
regarding Faraday Cage protective headgear will see this instead as  
solid evidence that the dreaded, functional pulse bomb - or even EMP  
ray-cannon - is already out there. ®
Bootnotes

*This breaks every rule of Acronym Club. We suggest Barrier Interposed  
Terawatt Countermeasures against High-powered Specialist Lightning  
Attack Pulses.

**Other than nuclear bombs, which produce a substantial EMP as a side  
effect when they go off. It has been suggested that if you wanted to  
EMP an enemy city - so knocking out all its comms and electronics, as  
opposed to leaving it a glowing glassy crater - you might touch off a  
suitable nuke above it in the extreme upper reaches of the atmosphere.  
Evil Sean Bean was fixing to do this to London in the Bond flick  
Goldeneye, using an eponymous Russkie space nuke pulse device hacked  
by Bean's henchmen from their thinly-disguised shopping centre base,  
apparently situated beneath the Arecibo radar telescope.