Summary: | This thesis addresses the evaluation of the apparent target background temperature difference (Delta Tapp) at maximum range and compares ATapp with MDTD/MRTD of a typical FLIR system. The atmospheric propagation code (SEARAD) and Planck's radiation law were employed to obtain atmospheric transmittance and path radiance. The atmospheric parameters were selected as close to the aircraft overflights as possible using PREOS 92 data as inputs of the SEARAD code. Ship target (R/V POINT SUR) modeling was established for MDTD/MRTD evaluation using a rectangular parallelepiped model of the ship's physical length, width and height. The geometry data for MDTD/MRTD evaluations were also selected from the PREOS 92 experiment measurement set. The MDTD/MRTD functions for a generic FLIR in wide field of view (WFOV) application were deduced from Shumaker. Johnson criterion was employed as a detection criterion. Resolution line-pairs at detection range to resolve the target have also been evaluated and compared against Johnson Criterion. The temperature differences between ATapp and MDTD at detection range show large scatter, ranging from 5% to 600%. They also show agreement with the same sensor altitude and viewing angle. A comparison of Delta Tapp with MRTD at classification range and identification range show that using NFOV would be more appropriate for target classification/recognition. Resolution line pairs at detection range derived from a typical WFOV MRTD curve show 10% to 5O% error for the eight runs, which is acceptable as compared against Johnson Criterion quoted as 1+/- 0.25 mRad.
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