本研究結合美國太空總署的GOLD（Global-scale Observations of the Limb and Disk）任務中搭載之紫外線成像光譜儀觀測資料，以及臺美合作FORMOSAT-7/COSMIC-2(F7/C2)衛星之IVM(Ion Velocity Meter)電子密度量測資料，針對赤道電離層中的電漿泡擾動進行統計分析，涵蓋 2021年太陽極小期與 2024年極大期的觀測結果。研究中將GOLD所觀測之135.6 nm大氣輝光影像轉換至APEX高度座標，並與IVM資料整合，針對日落後18–23本地時間(LT)計算擾動程度指標 σ 值（log 相對標準差），進行四種類型事件分類(Both detected、IVM only、GOLD only、Neither)。結果顯示，2024年的擾動事件顯著多於2021年，尤以南美洲地區20–22 LT的Both detected（GOLD與IVM同時偵測）事件最為頻繁。此外，若未針對輝光強度偏低或邊界區域進行濾除，容易導致GOLD σ 值過度放大，造成GOLD only（僅GOLD偵測）之誤判。透過投影至磁力線的APEX高度、邊界經度與輝光強度等條件篩選，可有效提升事件分類準確性。本研究亦初步探討 CYGNSS GNSS-R 延遲-都卜勒圖(DDM)資料中的缺值之空間分布特性，發現其於特定經度與本地時間區段與電漿泡活動具有對應性，具作為電離層擾動之間接觀測指標的潛在應用價值。綜合而言，本研究建構一套結合橫向與縱向多源觀測的高時空解析度電漿泡擾動分析方法，並針對不同太陽活動背景下的擾動行為進行比較，提供後續 GNSS干擾預測與太空天氣應用之重要依據。

Equatorial plasma bubbles (EPBs) are post-sunset ionospheric irregularities that disrupt trans-ionospheric radio propagation, degrading GNSS positioning and communications. This study integrates wide-field 135.6-nm airglow imagery from NASA’s GOLD mission with in-situ electron density from the FORMOSAT-7/COSMIC-2 (F7/C2) Ion Velocity Meter (IVM) to quantify EPB occurrence and variability under contrasting solar conditions (2021 near solar minimum; 2024 near solar maximum). GOLD scenes are mapped to an APEX framework and collocated with IVM orbital tracks in the post-sunset window (18–23 LT). A disturbance index, σ, defined as a moving-window logarithmic relative standard deviation, is computed along each track for both instruments. Events are classified into four categories—"Both-detected”, “IVM-only”, “GOLD-only”, and Neither—using thresholds of σ_IVM > 1% and σ_GOLD > 0.5%. To suppress false detections of GOLD observations of EPB in the regions of observation edge or low airglow radiance, we apply three quality controls: an APEX altitude ceiling, a longitudinal boundary margin, and a minimum background radiance filter. After filtering, cross-sensor agreement between GOLD and IVM improves markedly. Results show higher Both-detected occurrence in 2024 than in 2021, with pronounced activity over South America (≈ −60° to 0°) at 19–22 LT. For the detection using GNSS-R observation, an exploratory assessment indicates that elevated rates of NaN pixels in delay-Doppler maps (DDMs) derived by NASA CYGNSS show spatially coincidences with the known EPB-active sectors. This suggests that EPB might interrupt the GNSS-R signal making DDMs unable to be derived. Such characteristics could potential be an auxiliary proxy to detect EPB using GNSS-R. The framework and the results of this study offers a consistent, reproducible approach for multi-sensor monitoring of EPB which could support risk assessment of GNSS-dependent applications.

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