TOPOGRAPHICAL MAP GENERATING DEVICE EMPLOYING THREE-DIMENSIONAL INFORMATION OBTAINED BY INTERFERENCE TYPE SYNTHETIC APERTURE RADAR

摘要

PURPOSE:To generate a highly precise topographical map by compensating for the distortion of a three-dimensional topographical information expressed by the height data taken by an interference type synthetic aperture radar employing a specific method, transforming the coordinate system and compensating shadow. CONSTITUTION:An interference type synthetic aperture radar(SAR) computes the phase differences of SAR image data and converts the SAR image to height data 23 based on the attitude sensor data of a flying object. A foreshortening compensation section 18 of the topographical map generating device compensates for the front tilting phenomenon from the data 23. A pixel size compensation section 19 performs sampling of the output, i.e., three- dimensional data 24, based on a platform velocity information 29 so that the pixel sizes of range/azimuth become the same. Then, a geometric deformation compensation section 20 compensates for the geometric deformation of the output of the section 19 based on a Doppler center frequency 30. A coordinate conversion section 21 converts the output of the section 20 into the topographical map coordinates based on a GPS information 31. The output of the section 21, which is the shadow in the three dimensional information, is replaced by the data which are observed from a different direction.