導航衛星訊號具有高解析度與廣泛涵蓋之優點，其利用導航衛星訊號之反射進行遙測技術的應用在現今已有蓬勃的發展，包含偵測海面高度、海洋風場、地表含水量與冰層厚度皆屬於研究範疇。經由全球導航衛星系統反射訊號接收儀所產生的資料稱之為延遲都卜勒映射，一種可以去反映地球表面特性的觀測量。在過去已有大量的文獻在探討如何利用此一觀測量來去反演出海面的風場大小以及風速反演演算法的開發。現有的方法大多是著重於延遲都卜勒映射之能量大小來去做分析，但伴隨而來的問題就是衛星發射端的能量大小較難以估計，其影響將導致反演結果較不理想。本篇論文將以正在發展的獵風者衛星為基礎，利用其酬載設計的特色來去提出一個演算法，該方法利用同一時間所接收到的直視訊號和反射訊號的延遲都卜勒映射來當觀測量，利用這兩種觀測量來去求出通道響應函數，並依所得結果來做後續海面風速的估測。由於在直射端和反射端皆有共同的發射源，因此該演算法將有效地去消除發射端能量的影響。
本篇論文以多次飛行測試實驗所接收到的資料為基礎，針對這些獲得的資料來進行處理以驗證該方法的可行性且實驗的結果和分析也將會呈現在論文中。

Global Navigation Satellite System (GNSS) signal has advantages of good resolution and superior coverage. The application of reflected signals of GNSS has provided a significant boost for remote sensing nowadays. Applications including altimetry, ocean surface wind speed, soil moisture, and ice-layer density measurement are all within the scope of GNSS reflectometry research. The GNSS-R receiver can receive signals at from different paths and process the signals to yield delay Doppler map (DDM) or delay waveform which is an observable that can be used to retrieve various geophysical parameters of Earth’s surface. In the past decades, there have been a few studies discussing how to use 2-D delay Doppler maps (DDM) or 1-D delay waveforms to retrieve the ocean wind speed leading to the various development of wind speed retrieval algorithms. Existing approaches mostly focus on the power of DDM for analysis, but the accompanying problem is that the transmitted power is difficult to estimate. Thus, its influence will affect the quality and performance of wind speed retrieval. This thesis proposes a new method for data retrieval based on the TRITON GNSS-R receiver payload. The payload receives the direct LOS signal and reflected signal simultaneously and process the signals to generate direct LOS and reflected DDMs or delay waveforms. Subsequently, the channel response model can be constructed by utilizing the delay waveforms generated along the direct path and scattered path. A coefficient in the model is used as a new observable for the purpose of retrieving ocean wind speed. Both the direct LOS signal and reflected signal have the same source of transmitter. Thus, if we apply the proposed method, the variation of the transmitted power of the GNSS satellite will be eliminated and the quality of retrieved wind speed results may be enhanced. On the basis of the data received from a series of airborne tests, the proposed method were verified and the preliminary result would be presented. In addition, we considered different aspects of performance analysis, fitting models, GNSS PRN, and data buoys included, and some possible reasons for worse accuracy would be discussed in the end.

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