ARLA/CLUSTER: DARPA está a fazer experiencias com transmissores moveis em ULF (300 Hz a 3 kHz)

[João Costa > CT1FBF]

DARPA Ultra Low Frequency Radio

Defense Advanced Research Projects Agency (DARPA) is aiming for
personal mobile ultra low frequency transmitters to communicate
through water and soil

Radio frequency signals hit veritable and literal walls when they
encounter materials like water, soil, and stone, which can block or
otherwise ruin those radio signals.

With his newly announced A Mechanically Based Antenna (AMEBA) effort,
program manager Troy Olsson of DARPA’s Microsystems Technology Office
is betting on a little-exploited aspect of electromagnetic physics.

The plan is to use ultra-low-frequency (ULF) electromagnetic waves,
300 Hz to 3 kHz, which can penetrate some distance into media like
water, soil, rock, metal, and building materials.

Read the full story at
http://www.nextbigfuture.com/2016/12/darpa-aims-for-personal-mobile-ultra.html