Coordinate Time Series Analysis Of Anhui Province Continuously Operating Reference Stations

As one of the main means to promote the development of technology in the field of Surveying and mapping,GNSS has always been researched and concerned by scholars.With the mature of GPS technology,the state began to set up the continuous operation reference station system in the main city to serve the surve ying workers' work.The perfection of the CORS system makes the operation precision greatly improved,but the coordinates of the ITRF are constantly updated because of the internal and external environmental factors such as the pole shift,nutation,rainfall,plate movement and the implementation of the project.The coordinates of the same point are constantly changing under different epochs.There fore,the update and maintenance of the ITRF coordinate frame is becoming very urgent and important.The baseline between CORS reference stations is solved by GAMIT software,and then GLBOK adjustment is applied to get the single day solution coordinates of reference stations.After data interpolation,data quality checking,data coarse difference elimination,periodic term analysis,power spectr um analysis and noise model construction,the time series and velocity field model of reference station coordinate are obtained.The coordinate time sequence analysis of the CORS has high reliability for the influence factors and the analysis results of the whole research area because of the network characteristics of the CORS,sites quality,observation conditions,in strument,equipment,rainfall and lightning protection,so the velocity field can reflect the motion of the plate.features.The establishment of noise model and power spectrum analysis can better estimate the best noise combination of coordinate time series.The periodic term can give the periodic variation of the three direction components of the reference station coordinates.On the whole,horizontal direction has the shift to south-east direction.In the vertical direction,it has the subsidence in the north of Huai lake and relatively stable in the south of Huai lake.The above data processing and analysis laid the foundation for crustal movement and deformation in the distribution area of CORS site.