East Coast Exmo
Date: December 01, 2017 06:28PM
No one is messing with the Global Positioning System. If what you say were happening, it would make the international news. The system is heavily monitored, even by the commercial world, because so many people rely on it.
There would be no need to move satellites around to support a regional conflict because the system was designed to be "global". Also, it's the same satellites that transmit the military and civilian signals.
They don't degrade the "civilian" signal anymore because it would horribly affect a lot of innocent people and the military now has localized jamming capability: https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_Positioning_System#Selective_availability
However, it is possible that your friend was driving near a military base where they were testing jammers. Such jamming is scheduled and you can find notices of GPS outages here: https://www.gps.gov/support/user/#civilian
Or perhaps he's been driving near truckers who are operating illegal GPS jammers. Such things are readily available on the gray market, but extremely illegal to operate in the US.