Analysis Of GPS Station Coordinate Time Series And Discussion Of Abnormal Period Signal

With the scholars have studied the continuous operation of IGS(International GPS Service,IGS)stations worldwide at home and abroad,benefiting from the efficient development of the Global Positioning System(GPS),the structure / non-structure and anomalous periodic signals are endless,and there are colored noises and unusual slow slip phenomena in longer GPS coordinate time series.In order to better study the characteristics of GPS coordinate time series and GPS station reliability solutions,Obtain stable and reliable GPS station speed and its uncertainty parameters,and provide valuable reference materials for international hotspot research on continental structure.The paper selects PL,WN,GGM + WN,FN + RW,FN + WN,FN + WN + RW,and PL+ WN noise models for 72 consecutively operating IGS stations in the world from 2006 to2018.Abnormal periodic signals in the model and GPS time series are corrected by the PCA /KLE spatial filtering method to obtain stable and reliable GPS station speed and its uncertainties.The main research contents are as follows:1.Based on spatial geodetic data processing software such as GAMIT/QOCA,the GPS station data is solved to obtain the N,E,and U three-component site positions,velocity solutions,network parameters,coseismic deformation and other related parameters.GPS coordinate time series characteristic analysis provides reliable data support.2.Analysis of the characteristics of the GPS coordinate time series noise model.Based on the AIC/BIC noise model estimation criteria,the diversity noise model in the GPS coordinate time series is determined.The analysis results show that about 80% of the E component is the FN+WN model,and about 83.3% of the N component is the FN+WN model.The main component performance is about 53.3% for the FN+WN model and about 43.3%for the PL model.In addition,the influence of noise model on the speed and uncertainty of IGS station is further discussed and analyzed.The results show that the influence of different noise models on station speed is more obvious in the U component.3.Analyze the Episodic Tremor & Slip(ETS)phenomenon in GPS coordinate time series.Based on the 130-day parameters,the GPS station noise model,GPS station speed,and its uncertainty before and after ETS are analyzed.The results show that the presence of ETS has caused changes in the GPS station noise model,such as ETS front station PL+WN noise model was changed to the FN+WN noise model,which caused an incorrect estimation of the noise model,and the special GPS stations were marked.4.Analyze the spatially related errors in the GPS coordinate time series,that is,the common mode error(CME),and use the principal component analysis method PCA combined with KLE to filter the GPS coordinate time series to remove the common modeerrors in the coordinate GPS time series..In addition,through the PCA/KLE spatial filtering method,an abnormal periodic signal of about 1.04 cpy in the GPS coordinate time series was found,and the abnormal periodic signal was discussed.Furthermore,the annual motion of the GPS station coordinates(Seasonal changes)An analysis was conducted to pave the way for a deeper understanding of relevant geophysical phenomena.