在复杂地形条件下,SAR影像几何失真大,辐射畸变突出,透视收缩、叠掩和阴影等现象严重,制约SAR测图的应用。为此,提出一套基于多方向多源SAR数据融合方法与技术流程,利用不同侧视方向、不同分辨率、多极化的SAR影像数据,融合制作信息量丰富,能够满足应用要求的SAR假彩色正射影像。采用横断山脉区域3m分辨率的TerraSAR-X单极化影像以及8m分辨率的Radarsat-2全极化影像进行融合试验,制作假彩色正射影像。该方法、技术流程和软件已应用于国家西部1∶50 000地形图空白区测图工程。
SAR images acquired from some complex terrain areas present serious geometric distortions.Foreshortening,layover and shadow are usually extremely severe.The radiometric distortion induced by topographic relief is also strong.These factors limit the application of SAR mapping.Therefore,a new method and technical flow based on multi-direction and multi-polarization SAR data fusion was proposed according to complex terrain and inherent characteristics of SAR images.This method fused SAR images acquired from different looking directions,with different resolutions and multi-polarization to make color orthophoto map,which has richer information and could meet the needs of interpretation.A data fusion test was carried out using TerraSAR-X data with 3 m resolution and single polarization and fully polarized Radarsat-2 data with 8 m resolution in Hengduan Mountains to make the color orthophoto map.The method,technical flow and software module has been used in The 1∶50 000 Scale Topographic Mapping Project in West China.