應用經驗模態分解法估計DGPS修正量之研究

A Study on Differential GPS Corrections Estimated Using the EMD Method

林修國(Shiou-Gwo Lin) ； 蕭智文(Chih-Wen Hsiao) ； 王澔宇(Hao-Yu Wang) ； 蔡昆宏(Kun-Hong Tsai) ； 吳順德(Shuen-De Wu)

《航空太空及民航學刊.系列B》 44卷2期 (2012/12) Pp. 91-97

https://doi.org/10.6124/12-0803-702

摘要

全球定位系統（Global Positioning System, GPS）的誤差來源包含衛星誤差（星曆誤差、衛星時鐘偏差）、大氣影響（電離層與對流層影響）與接收器誤差（多路徑效應、訊號干擾、接收器時鐘偏差與熱雜訊誤差），利用差分定位（Differentail GPS, DGPS）可以減少衛星誤差與大氣的影響。DGPS利用已知座標的參考站估計距離修正量，並傳送該修正量給附近的GPS接收器，藉由修正共同誤差以得到更精確的定位成果。本論文利用經驗模態分解法（Empirical Mode Decomposition, EMD）來估計DGPS的距離修正量，並藉由比較與卡爾曼濾波器的成果，得知利用EMD估計DGPS修正量對於多路徑誤差與訊號干擾有相當優異的表現。

關鍵字

差分定位 ； 全球定位系統 ； 經驗模態分解法

並列摘要

The error sources of GPS include satellite errors (ephemeris error and satellite clock error), atmospheric errors (ionospheric error and troposheric error) and receiver errors (clock error, multipath error, interference error and thermal noise). The DGPS technique can reduce most of satellite and atmospheric errors. This reducing can significantly improve the accuracy of GPS positioning. The DGPS requires high quality GPS receiver at known reference stations and estimate the errors for each satellite in view. This correction is broadcast to all DGPS users by the Internet using the NTRIP standard. In this paper, a novel DGPS corrections estimation method based on EMD is proposed. The method is illustrated on real and simulated data, and the results are show great capability to reduce the effect of multipath and interference.

並列關鍵字

GPS ； DGPS ； EMD

參考文獻

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