For some time now, it's been known that if you pay attention to the carrier phase of the GPS signal, and if you have an Internet connection, then you can go from meter level to centimeter level, even millimeter-level positioning.
相当一段时间以来，我们都知道如果 你注意GPS的载波相位， 而且有网络连接的话， 你的定位精准度可以从米提到高厘米， 甚至毫米。