An Experimental Study on the Dependent on the Location for the Precision of the Network-Based RTK-GPS Positioning

The precision of a few centimeters can be easily obtained in 2drms of the horizontal positions by RTK-GPS positioning, as the range from a user GPS antenna to the satellite is determined by the phase measurement of the carrier waves. Since December 2000, it has been operated experimentally by the network-based system, known as the area correction parameter FKP (flächen-korrectur-parameter of the Geo++ GmbH in Germany) system in Kanto area. Now, the authors tried the network-based RTK-GPS positioning using the data transmission via the cellular phone every second at several fixed points, located inside the reference station network area, simultaneously. They investigated the dependent on the location for the precision of them. 2cm+(base line length)*2ppm cm in 2drms of the horizontal positions and S.D. of altitude measurements are similar to the RTK-GPS positioning. We must improve the network-based RTK-GPS precise positioning in order for it to be used by most people more easily.