Posted on 06/07/2016 9:25:27 AM PDT by MarchonDC09122009
FAA Warns of GPS Outages This Month During Mysterious Tests on the West Coast
http://gizmodo.com/faa-warns-of-gps-outages-this-month-during-mysterious-t-1780866590
The answer is staring you in the face, but you can’t see it because you are brainwashed.
What GPS does not do: GPS does not penetrate solid walls or structures well. It does not penetrate Earth. So signal strength becomes inadequate when you are in steep canyons, surrounded by tall buildings like in big city streets, or indoors or caves. Or if someone has a transmitter that is blasting noise on the carrier frequency.
If you have experienced this in Mexico and it was actual jamming, the only thing I could guess at was that south of the border, where the FCC cant enforce its rules, some cartel types could conceivably use jammers to frustrate law enforcement. But I doubt that's the case.
I don’t know what makes you so stupid but it really works.
What a retarded child.
It’s your GPS. Get one that’s intended to be international.
“Then please explain the bit about the signal disappearing as you drive south into Mexico.”
I’ve used GPS in Mexico, Bolivia, and Paraguay. As long as my antenna can “see” three sats I’m OK.
The signal can be obscured by clouds and rain but the sig definitely comes from the GPS constellation.
DGPS is a system that uses ground-based transmitters to enhance the 17 meter accuracy of GPS, DGPS is definitely ground-based, but sat GPS coverage is pretty much global except for parts of Antarctica where the birds are too close to the horizon to get three at a time.
http://www.gpsinformation.org/dale/dgps.htm
Bingo!
Mom and I used paper maps on our last big road trip. We only turned the GPS on occasionally, to verify where we were if there weren’t enough landmarks. We got there and back, and had a wonderful time.
A few times during the drive, we’d comment about people my age who couldn’t read a map to save their life. It’s a little disturbing how techno-dependent my generation has gotten!
Valuable elaboration.
For persistent Flat-Earthers:
Yes, I’ve also used my satellite based GPS in very remote moutains, valleys, canyons, south of the border down to Chile and even in Nepal.
GPS is most definitely satellite based, as was the Delorme Iridium satellite phone that helped save my life in a remote mountain ravine a few years ago.
Geez
I’ll use GPS but honestly find the voice prompts distracting while I’m driving. I usually study the route beforehand, and have it on with the sound turned off just in case. I guess I’m just too old-school, lol.
Wow, you need to adjust your tin-foil hat.
The GPS system is satellite-based, although there are ground-based augmentation systems that essentially broadcast a correction: the ground station is at a known position, and broadcasts the difference between the known position and the position measured via GPS. GPS receivers apply this correction and display a more accurate position. It's known as D-GPS, or differential GPS.
GPS satellite transmissions are very weak, just above the noise floor. So, it takes a sophisticated receiver with lots of signal processing to lock on to it. As a result, a ground transmitter can easily interfere by simply broadcasting noise on the GPS downlink frequencies. A stronger signal will interfere over a wider area.
Also, the DoD has the ability to control the satellite constellation over a specific area of the Earth. GPS satellites can degrade the accuracy by introducing random error into the signal, and by doing so for all satellites as they pass over a particular part of the Earth, the GPS constellation becomes less useful or even useless in that area.
The DoD has done this over war zones where they may or may not be operating. But, military GPS receivers are not affected, because they use a separate encrypted signal.
Even at the poles you can get more than 4 at any time. You can solve for lat/long with 3, but you need 4 or more to solve for lat/long/altitude. You are actually also solving for time in both cases (number of range equations equals number of unknowns, for those that are interested in the math. At least that’s the academic way of looking at it. In practice its done with matrix equations and least squares, for those interested in even more complex math).
Perhaps the info you have is dated to when the constellation was not built out. There are almost always 30 to 32 GPS satellites up and running at any time these days.
I seem to remember this happening last year too.
GPS jammers are widely available. You can buy them on the 'Net, or build your own. They are illegal, but that hasn't stopped people from using them.
There was a case a few years ago in NJ: GPS reception around the Newark airport area was having an outage every day, about the same time. They set up direction-finding equipment, and identified a truck that was carrying a jamming transmitter.
It turned out the driver was using it to jam the GPS tracking device in his truck, so his employer wouldn't know what he was doing.
No one is explaining exactly what is going on, but I suspect the DoD is not testing jammers -- they are testing GPS receivers that are intended to be resistant to jamming.
Then whatever will those who have to have their cute kitty videos do?
Our military trains to fight in the GPS denied environment more and more as the sophistication of our adversaries increases.
GPS is a great tool in warfare and spawned its own industry in the civil world, but its is also a big target that our adversaries consider a vulnerability. So our guys are working on ways to perform their duties with and without it.
They’re all enemy agents anyway, getting secret messages inbetween frames ;)
Can’t jam a compass.
I know where this is! 17/81 Split in Kirkwood NY!
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