Goldstein濾波參數探討－以SNAP為例

Discussion on Parameters of Goldstein Filtering Function of the SNAP Software

吳彥誼(Yen-Yi Wu) ； 任玄(Hsuan Ren)

《航測及遙測學刊》 27卷4期 (2022/12) Pp. 213-236

https://doi.org/10.6574/JPRS.202212_27(4).0002

摘要

相位濾波是採用合成孔徑雷達干涉技術一項必要的步驟。本研究使用SNAP軟體進行Goldstein濾波，探討之研究問題有二：（1）Goldstein濾波之各項參數對干涉圖所產生的影響；（2）十字圖樣之生成原因、初步分析十字圖樣對精度的影響。本研究成果顯示：（1）適應性濾波指數及快速傅立葉轉換大小對濾波強度的影響最顯著。（2）濾波強度增強，雖可以達到降雜訊的效果，但同時也會增加十字圖樣；當相位圖中的十字圖樣過多，會對干涉圖的影像判釋及最終精度都造成巨大的破壞，因此使用者應依據實驗區域的狀況酌情調整濾波強度，以取得降雜訊及十字圖樣間的平衡。

關鍵字

合成孔徑雷達干涉技術 ； 相位濾波 ； SNAP軟體 ； 十字圖樣

並列摘要

Phase filtering is one necessary step in the Interferometric Synthetic Aperture Radar (InSAR) procedure. In this study, the Goldstein Filtering function of the SNAP software was used. The research questions to be explored are two: first, the influences of adjustable parameters of the Goldstein Filtering on the interferogram; second, the cause of the ＂cross-like patterns＂ and the initial analysis of their impacts on the accuracy. The results has shown that: first, adaptive filter exponent and FFT size possess the most significant effect on the strength of filtering. Second, although enhancing the strength of filtering could reduce speckle noises, it will also increase the cross-like patterns. If there are too many cross-like patterns in the interferogram, it will undermine image interpretation and the accuracy of the InSAR final products. Therefore, users should adjust the filtering parameters appropriately according to the conditions of the experimental area, so as to achieve a balance between the noise reduction and the existence of cross-like patterns.

並列關鍵字

Interferometric Synthetic Aperture Radar Technique ； Phase Filtering ； SNAP Software ； Cross-like Pattern

參考文獻

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