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A new airborne multispectral scanner system was assembled and installed in a De Havilland DHC4A (Caribou) aircraft. This system was used to collect two sets of imagery; one set for strategic target areas near Sunnyvale, California, and another set for target areas near Rome, New York, during the time period July-November 1978. The imagery was processed and distributed to various researchers for use in studies of advanced scene-matching techniques as part of a program to provide precise autonomous guidance for strategic delivery vehicles. The sensor system produces seven data channels, all in spatial registration-visible, near infrared, thermal infrared, 1.06 μm laser reflectance, 10.6 μm laser reflectance, 95 GHZ radar reflectance and 1.06 μm laser range. All optical channels had a 1.25 mrad field of view and the radar has a 7 mrad two-way antenna beamwidth. The data were digitized and re-corded on a high-density digital magnetic tape recorder along with aircraft altitude from a radar altimeter and aircraft attitude and acceleration data derived from an inertial navigation sensor. A nine-inch format metric camera was boresighted with the sensors and provides additional information on aircraft position through use of inscene surveyed benchmarks. A key feature of the system was the dual-frequency modulated 1.06 μm laser ranging unit that provides absolute range from the aircraft to each pixel in the scene. The range data, the camera photos, and the inertial navigation data all provide inputs for geometrical reformatting of the imagery to remove distortions caused by aircraft motion and reconstruction of imagery either in the original line scan format or a single point-of-view format. The topic of the paper is the calibration aspects of this data base with the major emphasis being placed upon the geometrical reconstruction of the data.*
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