HR: 0800h
AN: G21A-1260 [Abstracts]
TI: A Study on the Relationship between the Surface Meteorological Measurements and the Precision GPS
Height Determination
AU: * Wang, C
EM: carlwang.cv87g@nctu.edu.tw
AU: Liou, Y
EM: yueian@csrsr.ncu.edu.tw
AB:
The accuracy of the Global Positioning System (GPS) positioning has been improved considerably during the past two decades.
With the present state-of-the-art of GPS data analysis in geodesy, GPS positioning accuracy is on the level of 1V2 mm in
horizontal coordinates and 5V10 mm in the vertical coordinate. The main error sources such as ionospheric refraction,
orbital uncertainty, antenna phase center variation, signal multipath, and tropospheric delay have been reduced
substantially, if not eliminated. In this study, the GPS data collected by the GPS receivers that were established as
continuously operating reference stations by International GNSS Service (IGS), Ministry of the Interior (MOI), Central
Weather Bureau (CWB) and Industrial Technology Research Institute (ITRI) of Taiwan are utilized to investigate the impact of
troposphere on GPS positioning determination. The surface meteorological measurements that were concurrently acquired by
instruments co-located with the GPS receivers include temperature, pressure and relative humidity data.
A hydrodynamic ocean tide model (GOT00.2 model) and solid earth tide were used to improve the GPS height. The surface
meteorological data (pressure, temperature and relative humidity) were introduced to the data processing with 24 tropospheric
parameters. The results from the studies associated with different GPS height were compared for the cases with and without a
priori knowledge of surface meteorological measurements. The finding based on the measurements in 2003 is that the surface
meteorological measurements have an impact on the GPS height. The associated daily maximum of the differences is 1.07 cm for
the KDNM station. The impact is reduced due to smoothing when the average of the GPS height for the whole year is considered.
DE: 0399 General or miscellaneous
DE: 1699 General or miscellaneous
SC: Geodesy [G]
MN: Fall Meeting 2005