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Probably just as easy as it is to jam yours

Here's an article in a trade publication about how an entire harbor was jammed. Culprit turned out to be TV antenna pre-amplifiers.

It's possible that a UWB system could interfere with these, but your UWB transmitter would have to be very close to your cell phone or TV.

Also, the signal strength as received by a GPS unit is incredibly low - very close to undetectable. It doesn't take much to disrupt them. In fact a month or so ago there was a NOTAM for a GPS outage in Phoenix AZ over a three day period. No reason was given but it is assumed that a new satellite was being tested at Motorola's satellite assembly facility - enough to shut down GPS in the entire county.

Here's a more complete article: GPS World.

sPh

sPh

this is nothing new at all. You're being a bit vague when you say it's a "new standard." Think of it more like a report on the current state of GPS for civil users; the DoD is simply saying that their old estimates of average performance were off and they're correcting themselves. The numbers in that report only reflect what can be done right now with GPS (in terms of a stand-alone receiver, no differential GPS).

The next real improvement in GPS accuracy will come with the launching of the next few blocks of satellites (IIR, IIF, III). The Block III satellites aren't slated to be deployed until at least 2010 and will include the new M code for more accuracy. Even sooner, the Block IIF satellites will support the new L5 channel for civil users which will give the public sector a big improvement in their accuracy. The C/A code (for public users) will be turned on L2 in the release of the IIR satellites starting in a couple of years. Up to now, the L2 channel was only for P(Y) code which public GPS users didn't have access to (P(Y) is the military PPS code (precise positioning service) and is heavily encrypted). And more improvements will be made as the OCS (operational control segment - the Air Force group that monitors and controls the GPS constellation) that will make GPS even more accurate and reliable.

But don't expect any more significant improvements in GPS accuracy until these new blocks of satellites are launched. Of course, these improvements exclude things like WAAS and other differential GPS solutions which will give a much more precise position solution than any single receiver can accomplish.

Here's a good page describing some basic GPS terms I used. Also, for a good summary of the lastest GPS modernization efforts, read this article.

t.

this is nothing new at all. You're being a bit vague when you say it's a "new standard." Think of it more like a report on the current state of GPS for civil users; the DoD is simply saying that their old estimates of average performance were off and they're correcting themselves. The numbers in that report only reflect what can be done right now with GPS (in terms of a stand-alone receiver, no differential GPS).

The next real improvement in GPS accuracy will come with the launching of the next few blocks of satellites (IIR, IIF, III). The Block III satellites aren't slated to be deployed until at least 2010 and will include the new M code for more accuracy. Even sooner, the Block IIF satellites will support the new L5 channel for civil users which will give the public sector a big improvement in their accuracy. The C/A code (for public users) will be turned on L2 in the release of the IIR satellites starting in a couple of years. Up to now, the L2 channel was only for P(Y) code which public GPS users didn't have access to (P(Y) is the military PPS code (precise positioning service) and is heavily encrypted). And more improvements will be made as the OCS (operational control segment - the Air Force group that monitors and controls the GPS constellation) that will make GPS even more accurate and reliable.

But don't expect any more significant improvements in GPS accuracy until these new blocks of satellites are launched. Of course, these improvements exclude things like WAAS and other differential GPS solutions which will give a much more precise position solution than any single receiver can accomplish.

Here's a good page describing some basic GPS terms I used. Also, for a good summary of the lastest GPS modernization efforts, read this article.

t.