The present system uses GPS-based stations as the
reference. Next, the authors investigated how the two
groups of fixed positions agree, by using CMR data
transmitted from the different two GPS-based stations.
They tried RTK-GPS positioning simultaneously with
two receivers and a single antenna, using CMR data
transmitted from Nerima and Kawasaki GPS-based CS.
The base line length is 17 and 16 km, respectively.