Abstract: The regional environment and climate of Bohai Rim are complex and changeable. Geology and geomorphology vary in different areas and regions. It is particularly important to explore the change rule of GPS station time series and the main noise types and spectrum law in this region. Based on accumulated data of GPS station in last years, this paper obtains the coordinate time series for each station by calculation and adjustment with GAMIT/GLOBK software, and analyzes the spectrum characteristics and periodic features using the Lomb periodogram method. At last, it studies the noise types of the station according to the linear fitting of frequency and power spectrum analysis. This article provides the theoretical basis for station time series denoising and further studies of the motion law of observation stations.

Key words: time series, Lomb periodic diagram, spectrum, noise type