Seasonal and short-term variability of multifrequency, polarimetric radar backscatter of Alpine terrain from SIR-C/X-SAR and AIRSAR data
Seasonal and short-term variability of multifrequency, polarimetric radar backscatter of Alpine terrain from SIR-C/X-SAR and AIRSAR data
复制标题
来自 SIR-C/X-SAR 和 AIRSAR 数据的高山地形多频偏振雷达反向散射的季节性和短期变化
DOI：
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发表时间：
2001
影响因子：
8.2
通讯作者：
H. Rott
中科院分区：
文献类型：
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作者：
D. Floricioiu;H. Rott
冰川和无冰地区的签名进行了分析，从极化合成孔径雷达数据在C-，L-和P-波段和单极化X-波段数据。该数据库包括1991年6月25日的AIRSAR场景和1994年4月和10月的SIR-C/X-SAR图像（SRL-1和SRL-2），这些图像是在奥地利高山试验场O/spl uml/tztal上获得的。三次实验时的环境条件不同。地面测量、气象观测和后向散射建模是解释后向散射特征的基础。季节性差异主要是由于雪的存在或不存在以及其性质的变化。雪况的短期变化可以在C和X波段监测。对于无冰川地区，地表粗糙度在所有季节都对后向散射有主导影响。分析了平均后向散射系数和相关系数随入射角的变化关系。光谱和去极化比和HHVV相关系数的大小被选为多维特征向量的成分，用于研究目标的可分性。良好的分离性之间的积累和消融地区的冰川，而在无冰地区，表面粗糙度的优势限制了歧视不同的表面类型。通过与野外数据的比较，证实了后向散射的短期变化对冰川堆积和消融区域的分类具有显着影响。
Signatures of glaciated and ice free areas were analyzed from polarimetric SAR data at C-, L-, and P-band and single polarization X-band data. The data base includes an AIRSAR scene from June 25, 1991, and SIR-C/X-SAR images from April and October 1994 (SRL-1 and SRL-2), acquired over the high Alpine test site O/spl uml/tztal in Austria. The environmental conditions were different at the time of the three experiments. Ground measurements, meteorological observations, and backscattering modeling are the basis for interpreting the backscattering signatures. Seasonal differences are due mainly to the presence or absence of snow and due to changes of its properties. Short term variations of snow conditions can be monitored at C- and X-band. For unglaciated areas, the surface roughness has a dominant influence on backscattering in all seasons. The dependence of the mean backscattering and correlation coefficients on the incidence angle was analyzed. Spectral and depolarization ratios and the magnitude of the HHVV correlation coefficient were selected as components of the multidimensional feature vector for studying the target separability. Good separability was found between the accumulation and ablation areas on the glaciers, whereas on ice-free areas, the dominance of surface roughness limits the discrimination of different surface types. Short-term variations of backscattering have significant impact for the classification of accumulation and ablation areas on glaciers, as verified by comparisons with field data.