本研究主要是將GPS衛星接收儀整置於固定平台，設置於成功大學位於安南區之水工實驗所大型造波水槽上之三角鐵框架，整合右旋與左旋圓極化天線，接收將來自GPS之直接信號與地面或水面之微弱反射訊號，進行科學分析及應用研究。藉由微調接收天線使其可分辨來自GPS之直接與反射訊號，以獲取天線有效接收頻率與方位，再依此幾何方法，進一步利用各衛星與接收儀天線所在位置形成之對應投影，反推算所接收各組微弱反射訊號之地面或水面反射點位置。其中之接收處理方式，主要為應用GPS直接訊號與反射訊號之相位觀測量，比對其訊號強度、修正時間延遲量與大氣延遲量後，完成求解反射點位置與高程。在實驗研究與分析過程中，將妥適調整接收儀之軟、硬體，在訊號處理與測試階段，能達到有效控制直接與反射訊號之接收，以整數周波未定數求解法則，應用於求解相位觀測量之周波未定值，藉以提昇反射點之坐標位置與高程精度。另外亦設置水位計，分別以不同頻率紀錄水波之高度。
在實驗解算分析時，主要在於推求水面與天線間之距離，藉此推算水面波之高程，並比較水位計量測之結果，兩者比較相同度在90％以內。 The purpose of this research is to develop a highly integrated GPS receiver with RHCP and LHCP antennas mounted on an iron-frame to receive direct and reflected GPS signals. In order to successfully acquire and track weak reflected GPS signals from ground and water-surface, there are several designs must be analyzed. First of all, both RHCP and LHCP antennas are employed and adjusted so that direct and reflected signals can be acquired. Then, the height of antennas foot print can be solved by analyzing the carrier phase of observation. During receiving GPS direct and reflected signals, by comparing intensity of signal, modifying time delay and atmospheric delay, the position and height of the reflected point of the signal can be solved. Since the locations of the reflected points are the surface of the water, the pattern of water wave can be determined. On the other hand, the heights of water wave are recorded by the wave gauge simultaneously. The differences between the reflection heights of this GPS system and the record of wave gauge are almost identical within 90%.
