Is the GPS we use a real GPS?

American GPS, of course. At present, only GPS can really provide positioning service in the sky. Gronas has almost no civilian version, Galileo has not yet networked, and Beidou is only in the experimental stage!

There is no extra charge for GPS! GPS is a broadcast signal, just like listening to a broadcast. After receiving several satellite signals, the receiver can determine its position. The manufacturer of GPS terminal equipment will extract the patent fee from the profit of product sales and pay it to the United States. The GPS service fee is one-off, which will be paid when you buy the machine, but there is an extra charge for updating the map!

For high-precision signals, the United States is encrypted, and we can't use it!