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Unorthodox links to the internet Signalling dissent
Economist ^ | March 25 2011

Posted on 03/25/2011 11:22:57 AM PDT by swarthyguy

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To: paladin1_dcs
While most of the time that signal comes from the keypad, it doesn't have to be that way all of the time.

Anyone possessing a functional cell phone has approximately zero security. Faraday cage might marginally improve that assessment.

There are ways to avoid giving away a transmitter. Not foolproof.

41 posted on 03/25/2011 10:06:45 PM PDT by bIlluminati (Don't just hope for change, work for change in 2011-2012.)
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To: Jeff Winston
Their fundamentalist islam philosophy can only compete where they can enforce it by violence.

The Romans believed that of the barbarians. They were right until the barbarians were inside the gates. The key to winning as the barbarians is a proper understanding of asymmetry.

42 posted on 03/25/2011 10:15:45 PM PDT by bIlluminati (Don't just hope for change, work for change in 2011-2012.)
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To: Myrddin
A high gain directional antenna on a CDMA phone would extend battery life since the transmitter would not have to run at as high a power level as with an omnidirectional antenna. Good for fixed operation.

Yes, that has been my experience, too.

Before that, I could hit a tower 40 miles away with an analog bag phone and a directional antenna, and did so often, working on oil rigs.

Digital was a pain because it was designed to work where there are sidewalks (close in), and I had to get a booster for the CDMA phone, adapters and hook that to the antenna. Without it the battery would die in no time, looking for signal.

The results were seldom as good as with the analog phone--more dropped calls or 'no service' moments, even if connections had less static.

Now AT&T has bought out my carrier and I have to change phones (GSM, now) and equipment yet again--and have it work the first time.

43 posted on 03/25/2011 10:32:42 PM PDT by Smokin' Joe (How often God must weep at humans' folly. Stand fast. God knows what He is doing.)
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To: swarthyguy
Looks to me the US policy elites decided to roll the dice, get rid of the old guard, and take their chances with the popular majority...

From the cheapseats, it looks like the policy elited defected to the Islamists.

44 posted on 03/25/2011 10:37:03 PM PDT by Smokin' Joe (How often God must weep at humans' folly. Stand fast. God knows what He is doing.)
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To: Smokin' Joe
CDMA works by having the tower send control information to the phone to ensure that each handset produces the same RF field strength at the receiving antenna. If you're a long distance from the tower or inside a building that attenuates the signal, the phone transmitter has to be run at a higher power level to achieve the expected strength at the tower. The rough value is set using the GPS location of the tower and the calculated GPS location of the handset. That coarse setting is then fine tuned based on the observed RF level arriving. A high gain antenna helps by directing the RF to the tower and reducing the amount of power required to achieve the required RF field strength.

TDMA/GSM doesn't have that same equal field strength constraint. It isn't trying to pick out a signal by correlation of a pseudo-random number stream unique to the handset. It does have other impairments. The stream is time sensitive and subject to Rayleigh fading when reflected multi-path signals mixed 180 degrees out of phase and cause signal dropout. Multipath actually helps CDMA by comparison.The multiple correlators expect out of phase arrival and leverage it as the PN streams are correlated and summed. I haven't looked at how LTE is implemented, but the move to 700 MHz should significantly improve penetration of signals into buildings.

45 posted on 03/25/2011 11:21:41 PM PDT by Myrddin
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To: Myrddin
We're being shifted from CDMA to GSM phones at the end of the month. 850 and 1900 Mhz, according to what they are licensed to use. How will that affect reception at a distance from the towers?

If it is too negative, I may have to change carriers.

46 posted on 03/26/2011 3:24:30 AM PDT by Smokin' Joe (How often God must weep at humans' folly. Stand fast. God knows what He is doing.)
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To: ShadowAce

Thanks for the ping


47 posted on 03/26/2011 8:13:33 AM PDT by GOPJ (http://hisz.rsoe.hu/alertmap/index2.php - It's only uncivil when someone on the right does it.- Laz)
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To: swarthyguy
Another way of confounding the authorities is to build portable FM radio stations. One broadcasting expert, who prefers not to be named but is currently based in Europe, is helping to develop a dozen such “backpack” radio stations for anti-government protesters ...

Resistance to skynet starts in an unlikely place...

48 posted on 03/26/2011 8:16:10 AM PDT by GOPJ (http://hisz.rsoe.hu/alertmap/index2.php - It's only uncivil when someone on the right does it.- Laz)
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To: martin_fierro

Thanks. Love it. The TechnoKB of FR is wonderful


49 posted on 03/30/2011 1:05:10 PM PDT by swarthyguy (KIDS! Deficit, Debt,Taxes! Pfft Lookit the bright side of our legacy -America is almost SmokFrei!)
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