Abstract
The differential Global Positioning System, DGPS, improves the user positioning accuracy based on correction
data computed of the reference station. The offset of the reference station, which includes an absolute
position erro, influences the user positioning accuracy. In addition, it is thought that in case of constructing a
personal DGPS system, the absolute accuracy of reference position influence user positioning accuracy. Authors
applied an intentional offset to the reference position, and quantitatively tested the influence of the reference
station offset on the user positioning. In this experiment, one GPS antenna was connected two GPS receivers
(one was for the reference and the other was for the user). DGPS measurement was done the baseline 0 m so
that other positioning error factors (e.g., multipaths, ionospheric delay, etc.) would not affect this experiment.
As a result, the reference point offset corresponded to the user measurement in the offset distance and direction.
In the case of constructing a personal DGPS, the absolute position of the reference station must be bighly
accurate.
