>>6963457 (lb)
RE: GPS SPOOFING
Ok . That I ain't got, but it's not terribly complicated to spoof with the right equipment. And it can be done with power output greater than actual bird in orbit, even with directional antennae making only target go astray.
The logical way to detect this spoofing would be to monitor abnormal signal strength of any of the satellites from what would be considered normal. ( a learning receiver could be engineered that would alert if signal is "too high" in comparison to what it has sensed in the nearby position in the past- would have to "relearn" if antenna were changed, etc. But would certainly detect the overriding signal as "too hot" for normal. )
There it is Q. Take my suggestion.
Forward to .MIL lab…