The Federal Communications Commission (FCC) is aware of this problem. Measures have been taken to punish the use of GPS jammer. These are small devices that send radio signals at the same frequency as GPS to cover or distort satellite signals.
Parkinson said: "The most serious threat is that your national agency permits ground transmitters to work with GPS frequencies. I have been fighting this issue for nine years.
"The FCC can license frequencies in a range close to those that would interfere with GPS. No one believes me, but they are so close. To do this, traffic congestion permits must be intentionally licensed and legalized."
However, if the GPS signal drops, there will be a lot of losses, not just consumers who rely on Google Maps for commuting. For example, the British Space Agency estimates that five consecutive days of GPS failure could cost the UK economy more than 5 billion pounds ($6.5 billion).