Hi Jim,
On 08/14/2017 06:03 PM, jimlux wrote:
And GPS users who care about spoofing tend to use antenna systems that
will reject signals coming from the "wrong" direction. It's pretty easy
to set up 3 antenna separated by 30 cm or so and tell what direction the
signal from each S/V is coming from.
I would expect that as spoofing/jamming becomes more of a problem (e.g.
all those Amazon delivery drones operating in a RF dense environment)
this will become sort of standard practice.
So now your spoofing becomes much more complex, because the sources have
to appear to come from the right place in the sky. (fleets of UAVs?)
You gain maybe 10 to 20 dB, but not much more.
A real protection scheme needs much more tolerance to handle severe
problems.
There is an overbeliefe in such approaches, rather than trying to look
at the system analysis, since when you loose the GPS signal, what do you
do. I get blank stares all too often when I ask that trick question.
Cheers,
Magnus
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