Frame Construction, The Gamit Software-based Gps Data Processing

The researchers of seismologists attach importance to use the data of the crustal deformation to study the inoculation procedure and regular of the earthquake, and last to forecast earthquake all along. The appearance of the observation technology of space observation cerate a new method to monitor the crustal deformation, especially the technology of GPS, taht has much superiorities such as high precision, small cubage of equipment, high efficiency, all day long, and so on. These superiorities are bringing the important change to the research of world and region's crustal movement. There is a great development on studying phenomena of earth dynamics by using GPS. More and more people involved in the areas of geodesy, geophysics, geology are using GPS technology to do research work..The software of GAMIT/GLOBK is one of the most economicl software to process GPS data with high precistion. Processing GPS data using GAMIT need the following steps:1, to prepare the observation GPS data;2,to edit and check the quality of the GPS data;3, to set the parameter file of the software of GAMIT and run the GAMIT software;4,to check the quality of the result that computed by GAMIT;5,to analyse the result further.The above procedure is inconvenient especially to the new hand. It is inconvenient to process GPS data with GAMIT/GLOBK that it is not easy to master this software. There are about over ten provincial earthquake administration beginning surveying with GPS data in our country, some of them have undergone for ten years, but there are fewer of them can process the GPS data well that it is difficult to process high precistion GPS data. This situation has limitted the development of GPS in earthquake research. It has immortant significance to explore more convenient method to process GPS data and make the technology of GPS to serve earthquake study with high performance which is one of the main objects of my graduate study.In the time of my gruaduate study,"China Main Land Construction Environment Monitor Network"project is constructing two hundred continuous survey stations, many of which will be constructed on earth. The GPS data with higher precision is better for earthquake research. It is a outstanding problem that the continuos earth station data can be used for earthquake research or not. The state key science project"China Crust Movement Survey Network"has constructed 25 continuous stations, most of which are set on rock . The Beijing area GPS continuous survey network has constructed 15 stations now. All of those are on earth expect the NKYU station. It provides good prospect for earthquake survey and crust movement research of Beijing district. In this paper will use the above data to study the problems if the data from earth stations could be used for earthquake research.In the light of above idea, we focus our study on the following aspects:(1) First of all, this article introduces the theory of GPS's technology, improvements, and application in the earth science; and introduces orientation theory of GPS, including coordinate and time system, basic observation and source of error.(2) Secondly, the method of GTK+ and it's multiple OS based programming are introduced. GTK+ is extensively used to write X Windows application code under Linux and other OS version of UNIX.It is difficult to set up GTK+ in Windows operating system. In this paper we introduce how to compile GTK+ under Windows operating system with MinGW and MSYS. The author advances one convinent method to show Chinese character in GTK+.(3) Thirdly, IGS service data downloading software are developed. IGS gives GPS client the high quality, high efficiency service and ensure the GPS technology reliably appling for research into accurate earth survey and earth dynamics. Although the data given by IGS is put in the open server regulaly, it is not easy to get data that you need. In this paper we give a client software to download IGS data specially. It can download navigation file, O-file, satellite orbit file, the result file of quality checing and h-file wich is used to GLOBK computing. Through long time test, this software is proved to be albe to download the file you need quickly when the network is well. It can show and solve the network bug. This software has been applied for daily GPS data processing in Earthquake Administration of Beijing. It satisfies the need of downloading IGS data, and its superiority is much obvious when downloading batch data( several month or one year).(4) Fourthly, to optimize the module of editing and quality checking for O-file. We mostly use the data processing software of TEQC to edit and check the quality of O-file. TEQC is based on the status of command-line so the interaction between the user and the software is not convinent. We achieved interface with C++ and GTK+, and enhanced work effeciency. Now only the QC2SKY software which runs under the Windows can lookover the quality checking result by the full star sky way, so it limits the Linux user to lookover the quality checking result by the full star sky way. In light of this status, the author reads the source of QC2SKY and developed a full starry sky graph looking software which runs under Linux with C++ and GTK+. This is the first full starry sky graph looking software under Linux.(5) To optimize computing GPS data module of GAMIT/GLOBK. The parameter files of GAMIT have regular form. If they are setted in the wrong way,GAMIT will export and give the information about error. But we can't find the cause of error relying on the information, that it is important to set parameter files right. Mostly we write shell script to run GMAIT module to compute GPS data, shell script is based on command-line, the interaction character is not well, and the shell script will be modified when the GPS project is changed, so it is not convenient to use. In light of this status, the author developed user interface with C++ and GTK+ which can edit parameter files directly, not needing to worry about the form. At the same time, the author acheved user interface to compute GPS data fit any GPS project. You can check the result precision directly after computing by using this module. It makes the GPS processing work conveninent.(6) The achievement of afterwards processing module. The author mainly developed the user interface module of extracting result data, editing result file and drawing time sequence graph and computing area of triangle and so on. It gave an convenient tool to analyse GAMIT running result.(7) The Primary use of continuous GPS earth station in Beijing. In the progress of processing GPS continuous station in Beijing, the author found that the variation of horizontal orientation of GPS continuous earth station is consistent with the rock station, but the vertical orientation is not the same as that rock station. In this paper the author use the GAMIT software to process the data of GPS continuous station in Beijing and 10 IGS stations around Beijing to discuss the possibility of using continuous GPS earth station to research in earthquake science.