Evaluating the Precision of GPS Positioning for Short Baseline Using Long-term Data
Jingnan Liu · Engineering of Surveying and Mapping · 2001
On the basis of a vast amount of GPS data (from June 1998 to December 1999) collected from GPS automatic monitoring system of outside deformation for Geheyan Dam, in this paper the 3- dimentional relative positioning precision for tow working datum marks about lkm long of this system was analyzed and evaluated. Results showed that the precision of 2h solutions was ±2.86 mm(NS direc- tion) ±2.50 mm(EW direction) and ±6.52 mm(U direction), that of 6h solutions was ±2.06 mm(NS direction)±1.77 mm(EW direction) and ±4.49 mm(U direction), and the precision in vertical compo- nent was about 2.5 times greater than in horizontal directions. The statistic analysis results had the char- acteristic oflarge Sample quantity, reflected veriy the 3-dimentional relative positioning precision for a single short baseline, and provided reference data for the design of GPS used for precise engineering sur- veying and deformation monitoring.