Theses and Dissertations at Montana State University (MSU)
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Item Infrared cloud imaging systems characterization(Montana State University - Bozeman, College of Engineering, 2016) Riesland, David Walter; Chairperson, Graduate Committee: Joseph A. ShawInfrared cloud imaging (ICI) is a useful tool for characterizing cloud cover for a variety of fields. Clouds play an important role in free-space high frequency (optical and mm-wave) terrestrial communications. Ground-based infrared imagers are used to provide long-term, high resolution (spatial and temporal) cloud data without the need for sunlight. This thesis describes the development and characterization of two ICI systems for deployment at remote field sites in support of Earth-to-space mm-wave and optical communication experiments. The hardware upgrades, calibration process, sensitivity analysis, system validation, and algorithm developments are all discussed for these systems. Relative spectral response sensitivity analysis is discussed in detail, showing as much as 35% calibrated scene radiance uncertainties when using generic manufacturer data in comparison with measured spectral responses. Cloud discrimination algorithms, as well as cloud phase (ice or water discrimination) algorithms are also discussed.Item Remote sensing applications of uncooled long-wave infrared thermal imagers(Montana State University - Bozeman, College of Engineering, 2012) Johnson, Jennifer Erin; Chairperson, Graduate Committee: Joseph A. ShawThe commercial development of microbolometer uncooled long-wave thermal infrared imagers in conjuncture with advanced radiometric calibration methods developed at Montana State University has led to new uses of thermal imagery in remote sensing applications. As a result of being uncooled, microbolometer imagers are notably lighter and cheaper than typical cooled imagers, making them ideal for remote sensing. Two novel uses are discussed in the work presented here. The first is the imaging of beehives in order to remotely determine the hive vitality. Bees thermally regulate their hives to a narrow range of temperatures that creates a thermal signature seen in thermal infrared images. For each of the hives imaged, frame counts (or the number of full frames of bees in each hive) were found by manual inspection. Linear regressions of the normalized frame counts of the hives were performed versus the measured hive thermal radiance values. The resulting plots showed a strong relationship between the normalized frame count and the mean radiance of each hive, particularly in images taken just prior to dawn. The second novel use was imaging vegetation exposed to large ground concentrations of CO ₂ over a four-week period in summer for use in leak detection. A CO ₂ leak was simulated in a test field run by the Zero Emissions Research and Technology Center. Thermal infrared images were acquired along with visible and near-infrared reflectance images of the exposed vegetation and healthy control vegetation. Thermal radiance statistics were measured and a regression was performed versus the day of the experiment. The infrared data were found to have a strong R ² value and clearly show the effect of the CO ₂ on the vegetation. An additional regression was run on the infrared data combined with the reflectance data, and this was found to not add any unique information to the vegetation reflectance data. Both methods were found to independently indicate the potential of a CO ₂ leak before it was detected visually.Item Wide-angle infrared cloud imaging for cloud cover statistics(Montana State University - Bozeman, College of Engineering, 2008) Nugent, Paul Winston; Chairperson, Graduate Committee: Joseph A. ShawThe Infrared Cloud Imager (ICI) is a radiometrically calibrated thermal infrared imaging instrument currently in development at Montana State University to measure cloud cover statistics. This instrument was developed originally as part of a joint U.S.-Japan effort to study the arctic atmosphere. The ICI provides localized high-resolution data relative to satellites images and, in contrast to visible imaging systems, provides continuous day and night operation. While the original instrument proved the capabilities of using radiometrically calibrated thermal infrared images to produce cloud coverage measurements, this instrument was limited. These limits were primarily the instrument's large size, relatively high cost, narrow field of view, and need to recalibrate the camera for each image. The work presented here covers work conducted to develop two prototypes of a second-generation ICI instrument, and the work which laid the groundwork for the development of a fully deployable version of these systems. These systems are to be used to measure cloud cover statistics for the characterization of optical communication paths by the Optical Communication Group at NASA JPL.