全球衛星導航系統反射訊號的應用在近年來開始蓬勃發展，成為發展性高的遙測方法，其應用也變得十分的多元，包含量測飛行器的高度以及量測各種地表的物理參數，包含海洋、冰層以及陸地。本論文實現一個GNSS-R接收機雛型體可以接收由地表反射的GPS訊號並對其作訊號處理。本接收機設計4個通道可以處理4顆不同衛星的反射訊號，另外也能夠蒐集數位中頻訊號進行後處理。另外，處理反射訊號時會發現處理後的結果，能量會有發散的狀況產生，其原因為處理反射訊號時會需要一段時間的積分讓能量能夠增強，不過由於積分時間長會因為電碼相位的變化使得積分後的訊號有發散的情況，於是本論文提出一個演算法來消除由於電碼相位的變化而造成能量發散的狀況，進而增加積分後的訊號強度。
本實驗的實驗結果分成兩個部分，其中一個部分為測試GNSS-R接收機是否可以接收以及處理反射訊號；另一個部分則是利用GNSS-R接收機雛型體搜集的數位中頻訊號來驗證本論文提出的演算法是否能夠解決由於電碼相位的變化造成訊號不集中的情況。

The application of reflected signals of Globe Navigation Satellite System (GNSS) has emerged in the last two decades as a feasible remote sensing tool in retrieving various geophysical parameters of Earth’s surface including ice layer, land, and sea. This thesis presents an implementation of a receiver that can receive and process GPS reflected signals. This receiver is designed to have 4 channels that can process 4 signals from different GPS satellites. Furthermore, this thesis also present an algorithm to eliminate the misalignment of reflected signals power. This problem occurs when using non-coherence integration to enhance reflected signals power. Because the non-coherence integration causes code phase shift, reflected power which is processed with coherence integration would not be aligned during processing non-coherence integration. This algorithm needs to use line of sight signals tracking to process reflected signals and use this method to eliminate misalignment of reflected signals power.
The experiments are divided in two part: one is to test the function of GNSS-R receiver (prototype) and the other is to verify that this algorithm would solve the problem of misalignment and enhance the reflected signals power.

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