DEVELOPMENT OF A GROUND-BASED SYNTHETIC APERTURE RADAR (GB-SAR)SYSTEM AND ITS APPLICATIONS TO ENVIRONMENT MONITORING ANDDISASTER PREVENTION

摘要

We have developed a ground-based polarimetric broadband SAR system for non-invasive ground-truth validation inrnpolarimetric SAR remote sensing of terrestrial vegetation cover. This system consists of a vector network analyzer, onerndual polarized antenna, and an antenna positioner. It can be operated in a frequency range from 50 MHz to 20 GHz,rnwith a scanning aperture of 20 m in the horizontal and 1.5 m in the vertical direction. Tests carried out with standardrnreflectors showed that the polarimetric measurement capabilities of this system are satisfactory. Using the polarimetricrnground-based SAR (GB-SAR) system, we carried out measurements on a specific vegetation cover pertinent to thernremote sensing of forested regions within Sendai City, consisting of three different kinds of trees common within thernKawauchi Campus of Tohoku University.rnThe same system can be used for interferometric use. Our test showed that the system can detect a deformation of thernsurface of a wooden building at the accuracy of less than 1cm. We also applied the same system for the monitoring of arnnatural cliff. The target was more than 50m apart form the radar location, and we could obtain the image of the cliff. Wernbelieve this system can be used for a real-time monitoring of the possible ground slide, and other targets such as largernconcrete constructions and buildings.