全球典型地物微波目标特性知识库

收集全球高分辨率光学影像作为知识库地理底图，这里我们采用的是MODIS数据得到的全球地物类型数据，数据分辨率为0.5°，收集全球地物底图的目的是通过对相似地物类型进行后向散射系数赋值，降低机载SAR和星载SAR数据成本；通过收集GF-3、Radarsat-2、Sentinel-1、Terra、Alos-1/2等星载SAR数据，对数据进行辐射定标并对已覆盖地区进行地物后向散射特性分析，得到不同地物后向散射系数。结合地理底图，对不同区域、不同时间的地物后向散射特性进行统计。根据得到的不同地物类型的散射系数值，基于地理底图对同类相近地物进行散射系数赋值，得到全球范围内典型地物微波目标特性库。

We collected global high-resolution optical imagery as the geographic base map for the knowledge base. Here, we utilized global land cover type data derived from MODIS data, with a spatial resolution of 0.5°. The purpose of compiling this global land cover base map is to assign backscatter coefficient values to similar land cover types, thereby reducing the cost of acquiring airborne SAR and spaceborne SAR data. By collecting spaceborne SAR data such as GF-3, Radarsat-2, Sentinel-1, Terra, and Alos-1/2, we performed radiometric calibration on the datasets and analyzed the backscattering characteristics of land covers in the covered regions, obtaining backscatter coefficients for different land cover types. Combined with the geographic base map, we conducted statistical analyses on the backscattering characteristics of land covers across diverse regions and time periods. Based on the acquired scattering coefficient values of various land cover types, we assigned scattering coefficients to analogous land covers of the same category using the geographic base map, ultimately establishing a global microwave target characteristic database for typical land covers.

搜集汇总

背景与挑战

背景概述

该数据集是一个全球范围的微波目标特性知识库，基于MODIS光学数据（分辨率0.5°）和多源星载SAR数据（如GF-3、Sentinel-1等），通过辐射定标和统计分析，获取不同地物的后向散射系数，并构建典型地物的散射特性库。其目的是降低机载和星载SAR数据成本，支持遥感反演应用，但目前数据尚未开放，需离线申请获取。