當全球導航衛星系統 (GNSS) 之頻段受到干擾時，全球導航衛星系統反射接收儀 (GNSS-R) 的延遲–都卜勒映射圖（Delay-Doppler Map）資料的訊雜比顯著下降，使得風速反演等典型任務難以展開。本研究針對此類資料開發全新應用，提出僅基於單一GNSS-R衛星延遲–都卜勒映射資料反推出窄帶單頻或多頻連續波類干擾源位置的方法。首先，針對此類干擾在延遲–都卜勒映射資料上呈現的條紋特徵提取都卜勒頻移，並參考相關文獻方法，利用最小二乘估計（LSE）構建同時包含都卜勒頻移與頻移率的代價函數；隨後於以經緯度–頻偏空間中進行網格搜尋以完成粗定位；最終採用梯度下降演算法，對發射源位置與頻偏參數進行精細定位。為驗證方法可行性，實驗分別以通用軟體無線電平台 (USRP) 產生模擬射頻訊號輸入獵風者衛星同款GNSS-R 接收機產生之延遲–都卜勒映射資料，以及獵風者衛星實際受干擾的延遲–都卜勒映射資料上進行測試。結果顯示，本方法將定位誤差控制在數十公里量級，可應用於干擾發射源的大範圍初步定位，輔助後續精準跟蹤。

When Global Navigation Satellite System (GNSS) frequency bands are affected by interference, the signal-to-noise ratio (SNR) of Global Navigation Satellite System-Reflectometry (GNSS-R) Delay-Doppler Map (DDM) data drops significantly, hindering conventional applications such as wind speed retrieval. This study proposes a novel use of such data: a method for locating narrowband continuous wave (CW) interference sources, whether single- or multi-frequency—using only DDM data from a single GNSS-R satellite. The approach begins by extracting Doppler shifts from the stripe-like features caused by the interference in DDM. Building on existing methods, a cost function incorporating both Doppler shifts and their rates is formulated using least squares estimation (LSE). A coarse localization is then performed through grid search in the latitude–longitude–frequency shift space, followed by fine-tuning using a gradient descent algorithm to estimate the emitter’s position and frequency parameters. To validate the approach, experiments are conducted using both simulated Radio Frequency (RF) signals generated with a Universal Software Radio Peripheral (USRP) and actual interference-affected DDM data from the TRITON GNSS-R satellite. Results show that the method can constrain the localization error to within tens of kilometers, making it suitable for large-scale preliminary localization of interference transmitters and aiding subsequent precise tracking.

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