NASA NTRS · 20210003257
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Lee, S., Portillo, A., Wright, M., Biswas, A.. 1999-09-21. Ground-ground Optical Communications Demonstration. https://ntrs.nasa.gov/citations/20210003257
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Purpose: a) Introduce candidate optical telescope assembly (OTA) architectures. b) Illustrate design/analysis process. Agenda: a) Definitions, Specification & Assumptions. b.) 4-meter Monolithic Mirror Concept. c) 6.5-meter Segmented Mirror Concept.
In this paper, a new crater detection algorithm is suggested. Experimental studies show that this new algorithm can achieve sub-pixel accuracy in position, its detection rate is better than 90% and its false alarm rate is less than 5%. These good characteristics indicate that it is an ideal crater detection algorithm for spacecraft optical navigation.
Optical systems, which operate over a wide range of Fresnel numbers, are often times performance-limited by diffraction effects. In order to characterize such effects at the 40-100 picometer level, a diffraction testbed has been built which has the capability of measuring diffraction effects at this level. Concurrently, mathematical diffraction modeling tools have been developed that propagate an input wavefront through an optical train, while retaining amplitude and phase information at a grid resolution sufficient for yielding picometer-resolution diffraction test data. This paper contains a description of this diffraction hardware testbed, the diffraction modeling approach, and a comparison of the modeled and hardware test results, which then serves as validation of the diffraction modeling methodology.