本研究藉由GPS反射訊號處理與現有高精度DTED Level 2數值高程資料庫整合應用於河川水文資訊的量測。研究過程以改良式GPS天線用以偵測並接收來自河川水面之反射訊號，再利用訊號處理方式將接收到之訊號進行反射點定位並求解河川水面高程值變化。而後透過數值高程資料之裸露河階地形比對GPS反射訊號所解算之高程變化，可進一步修正程式參數，以精算河川水面之高程變化，而求得更準確之水面高程。
此外，在訊號分析部份除了針對水面高程進行分析之外，我們也分析GPS反射訊號的都卜勒頻移值，利用速度場轉換的方式可計算出每個反射點的流速，而在此利用GPS反射訊號與數值地形資料庫整合應用，透過整合系統的開發將可提供全面性及近即時性的河川水面高程及流速的量測，更可加以估算河川洪水期之河水流量，用以提供河川洪峰流量之監控。

In this study, a novel scheme of river hydrological information measurement produced by reflected global position system (GPS) signals in combination with digital terrain elevation data (DTED) level 2 is presented here. The reflected GPS signals from river water level are obtained by ameliorated antenna. And the signals are computed into reflected trajectory points and water level altitude variations via a new application of GPS signal process. Afterwards the parameter reckoning water level altitude variation is amended on accuracy by contrast between DTED and results of processed signals
Besides, the Doppler value is analyzed to estimate the surface velocity of stream flow by velocity transformation matrix. And the integration can be applied to compute river water-level and velocity of stream-flow as monitoring fluvial discharge, especially during freshet.

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