Yes, it can be pretty trivially falsified. https://github.com/osqzss/gps-sdr-sim https://github.com/osqzss/gps-sdr-sim It can be done for probably less then a

Yes, it can be pretty trivially falsified. https://github.com/osqzss/gps-sdr-sim https://github.com/osqzss/gps-sdr-sim It can be done for probably less then a thousand dollars, even. It's also pretty trivial to detect the simple falsification schemes, but outside of exotic military and research projects, none of the easily available GPS SoCs bother.