RTK-GPS (Real Time Kinematic GPS) is a real time
satellite positioning system. The range to the satellite
from a user GPS antenna determined by the phase
measurement of the carrier waves from the GPS
satellites is of the order of mm in S.D. Thus the
accuracy of a few cm order can be easily obtained in
2drms. The system is easier to operate than such a
traditional system as ‘Total Station’. Many applications
have been investigated in Japan[1][2].