基于双极化差值指数的城市建筑用地信息提取研究

以福州市城区ENVISAT ASAR影像为例,研究城市建筑用地信息准确快速提取的原理和方法。通过对影像主要地物类型的极化特征分析,构建基于双极化雷达后向散射差值指数以突显城市建筑用地信息,并采用面向对象方法进行分类。该方法与基于单极化得到的分类结果相比,提高了精度。研究结果表明,该方法是一种快速准确提取城市建筑用地信息的有效方法,这为极化雷达影像数据在城市建筑用地方面的应用研究提供了一个新思路。

Study on extracting urban built-up land based on dual polarization difference index

In order to research the principle and method of urban built-up land information extraction,ENVISAT ASAR images in Fuzhou were used as an example to extract urban residential area.With the analysis of main land types polarization features,a polarization difference index(PDI) has been proposed based on dual polarization radar backscatter coefficient to enhance the built-up land information.Furthermore,object-oriented method was used to extract built-up land information.By contrast with the classification based on single polarization image,the application of PDI in the Fuzhou image has achieved a higher accuracy.This research result indicates that PDI is suitable for enhancing and extracting built-up land information,which can be applied as a new method to research urban by using polarization radar data.