利用短基線場檢測GPS天線相位中心之研究

Abstract

隨著全球定位系統逐漸普及與軟體處理技術日益精進，各種改良精度的模式相繼研發，天線相位中心變化模式的研究亦然。天線的相位中心並非固定不動，而進行GPS差分定位量測作業時乃相對於相位中心為準，因此天線相位中心將影響GPS測站相對高程與位移。基於各廠牌天線研發技術的不斷改良，甚至發展出零相位中心的天線，然而在實際外業操作中是否能夠達到此理想狀態則有待進一步研究。本研究利用短基線場上實施簡易旋轉GPS接收儀天線與後續幾何條件平差，應用短基線解算來探討天線相位中心偏移量，並討論最佳天線相位中心的基線解算模式。

In recent years, GPS technology has become available for everyone. With the addition of computer software, there has been remarkable progress with each passing day. As the study of correction models for GPS accuracy develops, the corresponding study of GPS antenna phase center models is also moving forward. In the practice of the differential GPS principle, the precise point is being measured from GPS is in proportion to GPS antenna phase center. However, the phase center of a GPS antenna is not a stable point. Therefore it affects GPS relative differential GPS positioning in vertical and horizontal. With more and more improvements in research on GPS antennas and even develop to the zero-phase center offset antenna. However it is still a question in daily GPS practice. It is therefore essential to prove the effect of zero-phase center offset antenna in the future. This thesis will discuss the antenna phase center offsets from GPS data by using unsophisticated geometry relationships of GPS antenna phase center, computing the deviation and adjusting it by the ‘Least Square Method’ in the short baseline field. It will also command a reasonable model to calibrate antenna phase center.