利用InSAR相干系数对SAR图像散射体特性的变化很敏感的特点,定义了一种相干系数变化指数,并证明了利用该相干性变化指数探测地震引起的城市破坏程度是可行的,最后以2003年伊朗Bam地区地震为例进行了试验验证研究。试验结果表明,建筑物的破坏等级与相干系数变化指数的大小高度相关,相干系数变化指数越大,建筑物破坏越大;相干系数变化指数相对较小,建筑物破坏较轻。根据定义的相干系数变化指数绘制出了Bam城地震破坏等级图,该等级图与国际地球灾害中心(ICG)提供的结果相一致。
A coherence change index was presented based on the sensitivity of the InSAR coherence coefficient to the change of the scatterer properties of SAR images, and the feasibility of detection of earthquake-induced urban damage by using the coherence change index was investigated. The method proposed was tested by the SAR images of the Barn earthquake in 2003. The results showed that the level of the earthquake-induced building damage was closely related to the coherence change index. The greater the index is, the more serious the damage is. Thus, the damage levels of the Barn city were mapped based on the index. The map was consistent with the results provided by the International Centre for Geohazards.