【正文】 Uses in calculates when the localization to need the satellite coordinates the broadcast star experience, the precision is (each satellite is different several meter to several dozens meters changes as necessary)。 S data storage center, IGS also nearly realtime synthesizes various data processing center the result, and the participant international earth rotation served the IERS global coordinates reference system maintenance and the earth rotation parameter issue. The user also may free online obtain product and so on observation data and precise star experience from internet. The GPS system realtime navigation pointing is very high, US has implemented the socalled SA policy in 1992, namely reduces the broadcast star to undergo the star position precision, reduces the star clock to change the positive number the precision, adds on the high frequency vibration to the satellite datum frequency (to cause false distance measuring accuracy to reduce with phase ), latter has implemented the AS policy, soon P yard change is Y yard namely further limits to the precise false distance survey, but American military and special permission user not these polices influences, but US in order to obtain the bigger mercial interest, these policy ends are cancelled.
2. GPS localization principal
The GPS receiver may receive and use in the time service accurately to the nanosecond level time information。附錄4燕 山 大 學(xué)課題名稱： 基于SPCE061A的汽車定位與防盜系統(tǒng)學(xué)院（系）： 里仁學(xué)院電子工程系 年級專業(yè)： 08級通信工程4班 學(xué)生姓名： 郭文杰 指導(dǎo)教師： 李朝輝 完成日期： 本科畢業(yè)設(shè)計（論文）外文翻譯外文翻譯原文
Summarizing The Global Positioning System Abstract: Global Positioning System is based on the background of the United States Department of Defense .It is designe, invested, developed, and operated by the United States Department of Defense, GPS is a satellitebased positioning and time transferring, GPS positioning function has a wide range of applications in the modern measurement and a more modern building. GPSRTK technology is also widely used in modernization building, and now GPS has also been shown to be an important civilian munity of interest, and increasingly wide range of applicated. Keyword: GPS, Locating, RTK, Lay out, Survey 1. Background
The 50s, the former has not launched humanities first artificial earth satellite, the American scientists in along its track research in, had discovered the Doppler shift phenomenon, and has facilitated Doppler satellite navigation positioning system pleting using this principle, has obtained the enormous success in the military and the civil aspect, was in a navigation localization history leap, our country once has also introduced many Doppler receiver, applied to the island association measured, the Earth explored and so on the applied to the island association measured, the Earth explored and so on the domain. But because Doppler satellite orbit highly low, signalcarrier frequency low, the track precision enhances with difficulty, causes the pointing accuracy lowly, satisfies the geodetic survey or the project survey request, is more impossible to use in the astronomy Earth dynamics research. In order to enhance the satellite positioning the precision, US started from 1973 to prepare for construction global positioning system GPS (Global Positioning System).After has entered the plan proof, the system test stage, started in 1989 to launch the official work satellite, and pletely pleted in 1994, investment use. The GPS system space is posed by twenty one satellites, evenly distributes in six 60orbit, the ground level is 20,000 Kilometers, the inclination of orbit is 55, the flat heart rate approximately is 0, the week contract is 12 hours, the satellite to the earth launching two wave bands intelligence signals, the intelligence signal frequency respectively is mega cycles per second (the L2 wave band), on the satellite has installed the precision very high atomic clock, guarantees the frequency the stability, modulates in the carrier has the expression satellite position the broadcast star experience, use in the range finder C/A code and Pyard, as well ad other system information, can in the global scope, to willfully multiuser provide the high accuracy, allweather, is continual, realtime three dimensional measures fast, the three dimensional localization and the time service.
The GPS system control section by is located in the American foundations of the states 5 monitoring stations to be posed, these stand did not ask breaks Carries on the observation to GPS satellite, and will calculate and the forecast information by the infusion stands renews to the satellite information. The GPS system user is extremely covert, it is one kind of oneway system, the user only receives but does not need the transmitting message, and therefore user39。下一期工作就是要將完成GPRS模塊的軟硬件聯(lián)調(diào)。另外GPRS模塊的程序運行沒有錯誤，但是軟硬件聯(lián)調(diào)還存在問題，無法按既定目標(biāo)正確工作。具有很強的現(xiàn)實意義。該GPRS模組具有：實現(xiàn)通過GPRS實現(xiàn)短信收發(fā)、短信鈴聲設(shè)置等相關(guān)功能。GPRS模組：配合44鍵盤、SPR模組、SPLC501鍵盤完成相關(guān)功能。該GPS定位系統(tǒng)具有：GPS信號搜索功能；利用SPLC501液晶模組顯示一幅中國地圖，當(dāng)GPS接收到信號后會在這個地圖上顯示當(dāng)前的位置；可以顯示當(dāng)前地理位置的經(jīng)緯度和GPS接收的標(biāo)準時間。即完成初始化，進入無限循環(huán)，其中所調(diào)用函數(shù)分別在其他模塊中實現(xiàn)。目前，已經(jīng)完成了：、GPRS模塊電路圖的繪制，以及主程序軟件程序流程圖的繪制工作；、GPS模塊的硬件連接和硬件調(diào)試；、GPS模塊的軟件程序編輯；、GPS模塊進行了軟硬件聯(lián)合調(diào)試。在這個設(shè)計中單片機控制GPRS讀取、發(fā)送短消息以及GPS 有效信息的獲取是整個軟件設(shè)計中需要注意的地方。經(jīng)過查閱相關(guān)資料和論文，確定了本次設(shè)計主要完成的功能是：通過GPS 模塊接收定位數(shù)據(jù)并由單片機處理，提取需要信息，并通過GPRS模塊將汽車位置信息，包括經(jīng)度、維度等，發(fā)送到用戶手機中。，進行電路調(diào)測；，進行軟件調(diào)試。，分為GPRS模塊，GPS模塊，震動傳感器防盜三部分。本階段的任務(wù)要求是：對基于單片機的車載定位防盜系統(tǒng)的設(shè)計方案進行全面了解、分析和設(shè)計。五、 主要參考文獻[M],2003年.,基于凌陽SPCE061A設(shè)計平臺的專業(yè)綜合設(shè)計教程[M].機械工業(yè)出版社，2007年.．16位語音型單片機SPCE061A實用教程—基礎(chǔ)篇[M].人民郵電出版社，2007年.—基于凌陽16位單片機應(yīng)用[M].北京航空航天大學(xué)出版社，2009年.[M].北京航空航天大學(xué)出版社，2003年. 6. 何立民．單片機應(yīng)用系統(tǒng)設(shè)計[M]．北京航空航天大學(xué)出版社，2000年.7. 胡漢才．單片機原理及系統(tǒng)設(shè)計[M]．清華大學(xué)出版社，1996年.8. 石東海．單片機數(shù)據(jù)通信技術(shù)從入門到精通[M]．西安電子科技大學(xué)出版社，2002年.,[J].微機原理與應(yīng)用,2004(2).10. 趙志禮 ,孟慶輝 ,張松濤 , 定位信息處理[J].電子測試,2009(10).附錄3.燕 山 大 學(xué)信息科學(xué)與工程學(xué)院本科畢業(yè)設(shè)計（論文）中期報告