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Studies On GPS Station's Coordinate Non-linear Movement And Its Causes

Posted on:2012-06-11Degree:MasterType:Thesis
Country:ChinaCandidate:L TianFull Text:PDF
GTID:2210330371462580Subject:Geodesy and Survey Engineering
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With the fast development of various space techniques, the accuracy and stability of ITRF is improving too. However, the ITRF's accuracy and stability should improve more for the demand of higher accurate earth dynamics surveying. So it has a great significance to analyze the ITRF stations'coordinate residuals series. Analyze the rule of residuals, and establish models to decrease parts of it. We made some study about GPS time series, distill the main non-linear periods, and establish models fitting. The main work is as follows:1,The definition of latest ITRF2008,ITRF2008 solutions and sites coordinate residuals series are reviewed. According to the simple analysis about sites coordinate residual series chart, we can see that there are some periodical vibrations in the time series.2,Make some data preprocessing about GPS coordinate residual series, and use two general ARMA model methods to fit the time series. And it fits very well. Then we make some compare about the two methods. According to the experimentation we can see that Pandit-Wu method is better when we have little dummy.3,Use the FFT and wavelet tool to separate the periodical rule from the residuals. Fourier fitting is a good way to fit the periodic terms. But there are some relative correlations between periods, so we can not fit all the periodic terms and it is not good compared with ARMA model. But it is a good way to analyze the periodic terms. The wavelet tool can also separate the periodic terms from residuals, but it is so complicated that we can just use it for validating the Fourier.4,According to the analysis of coordinate residual series, we can see that the annual change is a common rule , it is just different in amplitude of vibration. Other periodic terms are not in common.5,The geophysical reasons are discussed preliminarily. Use the SAS software to study the correlation analysis between periodic terms and temperature,atmospheric pressure,relative humidity. We find that the temperature's expands with heat and contracts with cold and atmospheric pressure affect the annul term greatly. The correlation analysis of atmospheric pressure is inosculated with international atmospheric pressure theory. The effect of relative humidity is very complicated because the effect of humidity to signal can not be computed.
Keywords/Search Tags:ITRF2008, coordinate residual series, time series, ARMA model, FFT, wavelet analysis, correlation analysis
PDF Full Text Request
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