SBIR-STTR Award

We propose to design and characterize an array of potential candidate reference sources suitable for infrared, visible and near-ultraviolet wavelength sensors that can be used to perform in-flight calibrations of DoD's signatures measurements assets. At Present, no flight-qualified reference sources exist for performing absolute radiometric calibration of these sensors while airborne. To accomplish this task we will first perform a study of DoD's airborne sensors that operate in the 0.2um to 15um wavelength regime and thus determine their in-flight calibration requirements. The instrument operating characteristics determined in this work will serve to define the reference sources needed which, in all probability, will include extended, point and intensity-modulated types. The proposed calibrators will be designed such that they can be installed into a standard SU-16 aircraft instrumentation pod and flown on (or along-side) the target aircraft whose signatures are to be investigated. The principal elements that are to comprise this prototype Airborne Common Calibration System (ACCS) are presented herein. Its design includes provisions for stand-alone operation (no pilot intervention required) and for recording of the important local atmospheric properties needed for post-flight interpretations of the calibration data acquired during airborne operations. This common reference system will fulfill a technology shortfall that presently exists in the evaluation of new and existing sersors intended for use onboard airborne platforms.

Keywords:
INFRARED SIGNATURES MEASUREMENTS ABSOLUTE RADIOMETRIC CALIBRATION IR/VISIBLE/UV CALIBRATORS AIRBORNE

At present, a technological shortfall exists within the DoD signatures measurements community for validating, while in the field, the response characteristics of many of its important test-and-development sensors. In particular, no measurement platform exists for in-situ performance validation during airborne measurements. We propose here to construct a mobile, flight-qualified calibration system housed within an Air Force SUU-16 instrumentation pod that can be fitted with specially-designed, modular reference sources and carried to operating altitude during measurement sorties. This Airborne Common Calibration System (ACCS) will also include provisions for recording of the important local atmosphere properties needed for post-flight interpretation of the calibration data acquired in field operations. The proposed approach can be considered to be an airborne analog to the very successful JTAMS ground-based common source. In Phase II we will acquire a flight-qualified pod and modify it with the baseline electrical and mechanical infrastructure needed to support the modular reference source approach. As proof of concept, we will build and install into the ACCS four radiometrically-calibrated reference sources. These are 1) an extended source for the 3 to 15 micron regime,2) a complementary TE-cooled extended source, 3) an ultraviolet-radiating extended source for 0.2 to 0.35 micron applications and 4) a UV point source suitable for the same wavelength range. For further applications of the ACCS, a store of calibrators can be developed from which program managers can then select the appropriate module (s)for the measurement task at hand. Design of the ACCS will be such that multiple sources can be simultaneously carried onboard.

Keywords:
SUU-16 POD CALIBRATION RADIOMETRY PHOTOMETRY SIGNATURES MEASUREMENTS