Type of Document Master's Thesis Author Coffey, Katherine Leigh URN etd-110398-161755 Title Next-Generation Earth Radiation Budget Instrument Concepts Degree Master of Engineering Department Mechanical Engineering Advisory Committee
Advisor Name Title Mahan, James Robert Committee Chair Priestley, Kory J. Committee Member Stern, Curtis H. Committee Member Keywords
- Monte-Carlo ray-trace
Date of Defense 1998-11-30 Availability unrestricted AbstractThe current effort addresses two issues important to the research conducted by the Thermal Radiation Group at Virginia Tech. The first research topic involves the development of a method which can properly model the diffraction of radiation as it enters an instrument aperture. The second topic involves the study of a potential next-generation space-borne radiometric instrument concept.
Presented are multiple modeling efforts to describe the diffraction of monochromatic radiant energy passing through an aperture for use in the Monte-Carlo ray-trace environment. Described in detail is a deterministic model based upon Heisenberg's uncertainty principle and the particle theory of light. This method is applicable to either Fraunhofer or Fresnel diffraction situations, but is incapable of predicting the secondary fringes in a diffraction pattern. Also presented is a second diffraction model, based on the Huygens-Fresnel principle with a correcting obliquity factor. This model is useful for predicting Fraunhofer diffraction, and can predict the secondary fringes because it keeps track of phase.
NASA is planning for the next-generation of instruments to follow CERES (Clouds and the Earth's Radiant Energy System), an instrument which measures components of the Earth's radiant energy budget in three spectral bands. A potential next-generation concept involves modification of the current CERES instrument to measure in a larger number of wavelength bands. This increased spectral partitioning would be achieved by the addition of filters and detectors to the current CERES geometry. The capacity of the CERES telescope to serve for this purpose is addressed in this thesis.
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28.8 Modem 56K Modem ISDN (64 Kb) ISDN (128 Kb) Higher-speed Access AppendA.pdf 30.66 Kb 00:00:08 00:00:04 00:00:03 00:00:01 < 00:00:01 AppendB.pdf 8.43 Kb 00:00:02 00:00:01 00:00:01 < 00:00:01 < 00:00:01 AppendC.pdf 27.07 Kb 00:00:07 00:00:03 00:00:03 00:00:01 < 00:00:01 Ch1.pdf 13.74 Kb 00:00:03 00:00:01 00:00:01 < 00:00:01 < 00:00:01 Ch2.pdf 26.81 Kb 00:00:07 00:00:03 00:00:03 00:00:01 < 00:00:01 Ch3.pdf 81.22 Kb 00:00:22 00:00:11 00:00:10 00:00:05 < 00:00:01 Ch4.pdf 1.90 Mb 00:08:48 00:04:31 00:03:57 00:01:58 00:00:10 Ch5.pdf 3.32 Mb 00:15:21 00:07:54 00:06:54 00:03:27 00:00:17 ch6.pdf 10.57 Kb 00:00:02 00:00:01 00:00:01 < 00:00:01 < 00:00:01 etd.pdf 21.41 Kb 00:00:05 00:00:03 00:00:02 00:00:01 < 00:00:01 References.pdf 17.06 Kb 00:00:04 00:00:02 00:00:02 00:00:01 < 00:00:01 vita.pdf 4.39 Kb 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01
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