[Asterisk-biz] voip e911 and homeland security

[trixter http://www.0xdecafbad.com]

On Mon, 2005-08-29 at 16:34 -0500, Matthew Boehm wrote:
> Andres wrote:
> 
> > Phones would have an embedded GPS receiver that pinpoints the location 
> 
> 	Yea, but I can block a GPS signal with my finger. Its no good unless 
> you are outside in the open. 99% of IP phones and ATA's will be inside. 
> No gps inside.

Because gps is used so readily for so many apps, I was actually thinking
about guilding a gps jammer.  100mW should do my vehicle fine or
anywhere near me, and because of FCC rules I should be able to get away
with that (I need to investigate the 'harmful interferance' clause to
100mW and below signals, although you can exceed that power if you lower
the duty cycle (ie pulsed transmissions), that should be fine.  Toss
some gaussian noise or similar on the L1 control freq (about 1622MHz if
memory serves) ...  only higher end gps receivers that use S1 control
data would get through, or the many many many many other satellite
networks that provide location data, but most receivers dont work with
those, at least in the consumer retail market in america.

The AF did a 'accidental' test with a 5w transmitter a few miles up in
the atmosphere and it totally hosed gps for everyone under that plane
(pretty wide beam path too).  I think it was an intentional test to
verify if jammers could be used to disrupt smart weapons, but they
insist that it was accidental.  :)

Who knows I may even be able to get FCC certified (unlikely) for the
jammers and sell them as personal security devices to prevent
stalkers/lovers (like the boyfriend that did that to his girlfriends car
to see if she was cheating) from tracking you.  Rental car companies
(hertz at least) that do this and issue speeding tickets if the gps data
says you went too fast or surcharges for going 'out of area' when you
were lost or ...  would have fits with these devices.  

I may have a research project for tomorrow going through part 68 and
maybe part 15 on the fccs site :)


-- 
Trixter http://www.0xdecafbad.com     Bret McDanel
UK +44 870 340 4605   Germany +49 801 777 555 3402
US +1 360 207 0479 or +1 516 687 5200
FreeWorldDialup: 635378
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