近年來，隨著全球定位系統(Global Positioning System ； GPS)的普及，GPS的觸角已悄悄進入我 們生活。車輛路線導航以及提升行車安全即為全球定位系統最廣泛的應用。在沒有任何校正下， 定位的誤差來自傳送端時鐘誤差，對流層延遲，電離層延遲，多路徑影響等等，造成了大約10到 15公尺之間的誤差。由差分定位等校正系統可以把誤差縮小至3到5公尺。然而這些校正系統均需 要使用到基準站，主控站及同步衛星等實體建置，且都是由主控站中央控制並提供誤差校正量給 移動站等使用者。本論文提出一種分散式的校正方法，不需基地站等昂貴設備，僅由協同式車間 通訊，利用不同車輛收到的GPS封包校正自己本身的位置，實驗結果顯示提出之演算法大幅改善 定位的精準度。

In recent years, the global positioning system (GPS) has been extensively used in the daily life. The most common application is a vehicular positioning device for planning and navigating the destination and promoting traffic safety. However, GPS has an error of about 10-15 meters without using calibration. The positioning errors are caused by signal arrival time errors, atmospherics effects, ephemeris errors, multipath errors, and other effects. The present calibration systems can reduce the position errors to 3-5 meters. But the systems not only have to set up the reference stations, the master stations, or the GEO satellites but also use a centralized method to provide the position correction data by the master stations. A distributed calibration method is proposed here to calibrate the GPS position according to cooperative vehicles. In this paper, we experiment our calibration method by using the realistic GPS data. The results show that the calibration method can improve the accuracy performance of GPS positioning notably.