應用時間序列分析於GPS多路徑效應之研究

Study on GPS Multipath Effects Using Time Series Analysis

江偉銘(Wei-Ming Chiang)

指導教授 ： 吳究

國立中央大學/工學院/土木工程學系/碩士(2008年)

摘要

在GPS短基線相對定位的應用上，使用二次差分可以消除大部分的誤差，多路徑效應誤差卻因測站間環境與衛星幾何構形的不同而無法去除。因此在高精度的GPS定位中，多路徑效應為主要的誤差來源之ㄧ。GPS定位精度的提升有賴於多路徑效應誤差的降低與消除，當衛星群幾何構形重覆出現時，多路徑效應具有重複性質。
本研究以GPS衛星群與接收天線間，每一恆星日的幾何重複性為基礎，探討GPS短基線定位的坐標時間序列特性，分析多路徑效應影響量與重複性，並使用恆星日濾波與最小二乘調和估計來降低多路徑效應的影響量，研究結果顯示這些方法在GPS靜態與緩速動態定位上，對於精度提升皆有正面的效益。

關鍵字

時間序列分析 ； 多路徑效應 ； 全球定位系統

並列摘要

Most of the errors affecting GPS positioning in short baseline are minimized by double differencing technique, multipath effects error will remain due to the highly site-specific nature of reflection of GPS signals from nearby surfaces. Accordingly, multipath effects error is considered one of the major errors affecting precise GPS positioning. Estimates of position using GPS are improved by removing multipath signals, which repeat when the GPS constellation appears again.
The foundation of this research is the geometry between the GPS satellites and the receiving antenna should repeat in every sidereal day. The objective is to discuss the characteristic of the GPS positioning time series and analyze the influences and repetitions of multipath effects. This error can be reduced by using sidereal filtering and least squares harmonic estimation. The result demonstrates that the accuracy of the GPS static and slow-moving kinematic positioning can be improved by these methods effectively in GPS short baseline.

並列關鍵字

GPS ； Multipath Effects ； Time Series Analysis

參考文獻

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