On 6/25/12 7:11 PM, Chris Albertson wrote:
On Mon, Jun 25, 2012 at 6:43 PM,<[email protected]> wrote:
Yeah, I read it. Typical Fox. The headline isn't accurate since they
spoofed the civilian GPS system, not the military GPS.
I think it is. Currently the military uses GPS guided drones put the
article says they will see more and more used, even by companies like Fed
Ex. I don't think I deliver this will happen soon but it might. The
article says that these new drones will be susceptible to GPS spoofing.
But there is a simple "fix" that to me seem obvious. When you design a
nab system for a drone they should use inertial nav. You can't spoof an
IMU. But the cheap IMUs drift and need GPS updates. So each time you
update the INU to do a sanity check on the GPS and see if it is within the
drift range of the IMU. If not you assume the GPS is being spoofed and
continue using the INU data.
And of course, this *is* the way almost every autopilot/nav system out
there works..
You use IMU+GPS... GPS is long term, but crummy in the short term; IMU
is good short term (e.g. to stabilize flight path), but crummy long term.
Not to mention that spoofing GPS is actually fairly hard to do,
reliably.. you have to have an internally consistent set of signals and
observables that seamlessly connects to the original natural set and
then walks off.
jamming is easy, spoofing is hard.
I would also expect that these things will very quickly go to L1/L5 for
"safety of life" applications, and spoofing 2 frequencies is just that
much harder.
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
