全球衛星導航系統反射訊號之應用於近二十年嶄露頭角，成為一有前瞻性的遙測方法，可用於反演各種地表物理參數包含冰層、陸地以及海洋。本論文探討由海面反射之GPS訊號，為確保左旋天線接收之訊號為海面反射而來，提出一個能夠辨識海面反射訊號之流程。此流程分為兩個部分，直視與反射訊號間延遲預測以及延遲估算。在延遲估算流程中，先設定一門檻值辨別可能為海面反射而來的訊號。並且，針對通過門檻值的訊號進行延遲的估算並比較延遲的預測值以及延遲的估算值，若兩者之值一致，則推定反射訊號辨識成功。
辨識流程中設定了兩個門檻值，載波雜訊比的標準差和延遲誤差，由多筆實驗以及資料處理結果算得。本論文的實驗結果包含兩次實驗於不同天進行，使用本文提出之流程，其反射訊號皆有被辨識出來。第二個實驗使用風速計測量風速資訊，用來模擬鏈路預算分析和延遲都卜勒映射。鏈路預算提供預測之載波雜訊比。而後，比較模擬結果與由實驗算得之載波雜訊比和延遲都卜勒映射，進一步證明所辨識出的訊號為反射訊號。

The application of reflected signals of global navigation satellite system (GNSS) has emerged in the last two decades as a feasible remote sensing scheme in retrieving various geophysical parameters of the Earth’s surface including ice layer, land, and sea. In this thesis, the GPS signals reflected off the sea surface are considered. To ensure that the signals received by the antenna are reflected signals from the sea surface, a procedure is proposed to detect and process the reflected signals. The procedure is composed of two parts. One is delay prediction and the other is delay estimation between line-of-sight signal and reflected signal. In the procedure for delay estimation, a threshold is set to identify candidate reflected signals from sea surface. Furthermore, the predicted delay and the delay estimation of candidate reflected signals are compared. If the difference between the predicted delay and the delay estimation is within a certain chosen threshold, the reflected signals are identified.
Several experiments are conducted and the received data are processed. Thresholds about standard deviation of C/N0 and delay difference set in the procedure are determined from this experiment analysis. The results in this thesis contain two experiments conducted on different days. In both cases, the GPS reflected signals from sea surface are identified using the proposed procedure. The wind speed information is measured by an anemometer in the second experiment. To correlate the results, the simulations of link-budget analysis and delay-Doppler map are made. The link-budget analysis provides the predicted C/N0 information. Thereafter, both simulation results are compared with the C/N0 estimation and delay-Doppler map extracted from experiment to further verify the detected signals are indeed reflected signals.

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