Abstract: The periodic and nonperiodic errors in coordinate time series of GPS stations have seriously affected the analysis of the characteristics of the stations and the explanation of the physical mechanism of the nonlinear motion. Therefore, in order to weaken the influence of noise, the region stack filtering method is used to remove the common mode error of the time series of 16 stations in Southern California, which weakens the periodic errors including annual and semi-annual errors in time series. In order to remove the residual noise after filtering, the filtered signals are subjected to static discrete wavelet transform processing, and the signals with the periods of more than half a year are extracted. The results show that the combined region superposition filtering method and wavelet transform can deal with the time series of GPS station coordinate time series, which can weaken the influence of periodic errors of the signal and extract the nonlinear motion signals of the station as well.

Key words: GPS station coordinate time series, common mode error, wavelet transformation, signal noise separation