GPS jamming in Flordia

[gatorman49]

Originally Posted by Cadence

I'm sorry if GPS jamming was some ones fear. Don't take your car out of the driveway. You might get lost.

Ouch, someone got up on the wrong side of the bed.

[zboss]

I'm still waiting on the reports of sailing ships crashing into the rocks or disappearing into the Bermuda triangle, never to be heard from again, because of GPS jamming... how many years now have we been hearing about this?

[gatorman49]

It’s just a discussion. Does it bother you that much?

[Jammer]

Survey says that GPS works better when jammed than celestial did on a clear night, at least for the typical sailboat navigator.


Other survey says that GPS jamming affects smaller areas for shorter times than celestial outages caused by the atmospheric phenomenon known as "clouds."


Sailor who keeps a navigation log with hourly fixes is well prepared for a transition to DR and pilotage

[SeanPatrick]

Originally Posted by Jammer

Survey says that GPS works better when jammed than celestial did on a clear night, at least for the typical sailboat navigator.

Except that the GPS might give no indication that its data is faulty. Whereas if you shoot several bodies and one has an intercept of 60 NM while the others are 5, you know something's gone wrong.



And you can use the sextant to make sure the GPS is accurate and vice versa. Or not. To each his own.

[Bycrick]

GPS jamming is an unlikely worry except close to shore. A 1+ GHz jamming signal won’t go very far unless you have a high-elevation, like a satellite. But it’s cheap and easy to do. If GPS is jammed, it just doesn’t work.

GPS spoofing requires sending the proper data formats rather than just the noise of jamming. Takes a lot more equipment and smarts, but it’s been done by college students for class projects. Again, it’s short range unless the spoofer has high elevation.

Bad GPS positions are almost always system problems on one end. Bad data or clocks in the satellites: rare but has happened. Bad software in the receiver, much more common. The real problem is that GPS is right so often, that we don’t recognize when it’s wrong until we hit something.