GPS觀測資料品質影響相對定位精度之研究

Study on the Relation between the Quality of GPS Observations an the Precision of Relative Positioning

葉大綱(Ta-Kang Yeh) ； 王傳盛(Chuan-Sheng Wang) ； 李瓊武(Chiung-Wu Lee)

《地籍測量：中華民國地籍測量學會會刊》 21卷2期 (2002/06) Pp. 14-27

https://doi.org/10.29609/YYWYLL.200206.0002

摘要

提昇GPS定位之精度一直是使用者所追求的目標，為達此目的，吾人著眼於探討GPS觀測資料品質與定位精度之相關性，期望能提供未來的使用者在選用GPS量測設備之參考。在本文中，吾人所採用的GPS觀測資料品質指標有四項，分別為L1載波的多路徑效應、L2載波的多路徑效應、每n個觀測量會產生一個過波脫落以及接收器內部時鐘與GPS時鐘的平均偏差量。由資料品質計算成果初步顯示，交通大學站的時鐘偏移量及多路徑效應較大，而陽明山站的週波脫落較為嚴重。在精度評估方面，則以每天解算的成果進行基線及坐標重現性分析。結果發現，週波脫落對於基線解算成果雖無顯著的影響，但對於測站垂直坐標上卻有著較大的影響，最大可造成2 cm的誤差，而接收器內部時鐘的好壞以及多路徑效應的大小只要在適當的範圍之內，並不會對解算的成果有太大的影響。

關鍵字

全球定位系統 ； 資料品質 ； 基線精度 ； 坐標精度

並列摘要

To obtain the better precision of GPS positioning is the goal for GPS users. For this purpose, we studied the relation between the quality of GPS observations an the precision of positioning. We hope to offer some information to GPS users, when they decide to purchase any GPS receiver. In this paper, we adopted four quality indicators of GPS observations. They are multipath on L1, multipath on L2, observations by cycle slips (o/slps) and clock offset for reference epoch. We found that multipath effects and clock offset were worse at the station NCTU, and o/slps were worse at the station YMSM. Evaluating precision with daily repeatability of baselines and coordinates, we found that o/slps were not a critical factor for the precision of baseline. Solution, but it was a very important factor for the precision of vertical coordinate, in which a maximum error of 2 cm was found. Clock offset and multipath effects, limited to a extent, would not be the critical factors to influence the GPS results.

並列關鍵字

Globe Positioning System ； Quality of Observations ； Precision of Baselines ； Precision of Coordinates