Remote Sensing Commons^™

Dynamics And Control Of Tethered Satellite Formations For The Purpose Of Space-Based Remote Sensing, Kurt A. Vogel

Theses and Dissertations

This dissertation assesses the utility of tethered satellite formations for the space-based remote sensing mission. Energy dissipation is found to have an adverse effect on foundational rigid body (Likins-Pringle) equilibria. It is shown that a continuously earth-facing equilibrium condition for a fixed-length tethered system does not exist since the spin rate required for the proper precession would not be high enough to maintain tether tension. The range of required spin rates for steady-spin motion is numerically defined here, but none of these conditions can meet the continuously earth-facing criteria. Of particular note is the discovery that applying certain rigid body …

Terrain And Spatial Effects On Hazard Prediction And Assessment Capability (Hpac) Software Dose-Rate Contour Plot Predictions As Compared To A Sample Of Local Fallout Data From Test Detonations In The Continental United States, 1945-1962, Kevin D. Pace

Theses and Dissertations

Hazard Prediction and Capability (HPAC) Software is validated by comparing modeled predictions to historical test data. Reanalysis weather data is acquired and reformatted for use in HPAC. Simulations are made using various amounts of weather data by use of a spatial domain. Simulations are also varied by levels of terrain resolution. The predicted output of the software is numerically compared to historical test data. The result of this research culminated in the knowledge that HPAC prediction accuracy is improved by using terrain resolutions beyond the flat earth assumption. Furthermore, this research establishes that domain size variation produces no significant advantage …

Modeling And Simulation Of Commercial Satellite Imagery Processes, David A. Shultz

Theses and Dissertations

The purpose of this research was to develop a general, statistical model of order-to-delivery times for commercial satellite imagery. The research looked at the current four satellite providers with 3-meter or better imagers in the context of a generalized model of commercial imaging satellite operations. Existing methods use orbit analysis tools to determine the imaging time of a specified target based on defined satellite position and times, but can only develop shortest and longest times to an imaging opportunity. To address the general question of the time it takes to deliver an image for non-specific targets, this research develops a …

Simulating A Chromotomographic Sensor For Hyperspectral Imaging In The Infrared, Anthony J. Dearinger

Theses and Dissertations

Hyperspectral imaging systems passively sense radiant electromagnetic energy from a remote scene to form a three dimension profile of the remote scene. The data contained in this profile describes real images of the remote scene for a certain number of spectral wavelength bands across a finite spectral range of electromagnetic radiation. Typical grating type hyperspectral imaging systems collect spectral electromagnetic radiation in the visible and near infrared spectral range, by incrementally scanning across the spatial extent of the remote scene. The legacy of low optical throughput because of the optical scanning techniques employed in these systems means adapting these systems …

Atmospheric Water Vapor Lidar Measurements Using Analog And Photon Counting Techniques, Anuj Maheshkumar Shah

Electrical & Computer Engineering Theses & Dissertations

Atmospheric water vapor measurements are essential for the understanding of Earth's weather and radiation budget, along with the water cycle. The remote sensing Differential Absorption Lidar (DIAL) technique is a commanding method used for water vapor measurements from aircraft, spaceborne, and ground-based platforms. The new unmanned aerial vehicle (UAV) water vapor DIAL system provides great feasibility due to the weight and size limitations. The system has significantly less weight, power consumption, and noise presence, thus making it great for UAV applications.

This thesis discusses a UAV water vapor DIAL system that was designed, developed, and evaluated. The research effort was …

Commercial Regional Space/Airborne Imaging, Ugur Akyazi, Ali Durmus, Birce Boga Bakirli, Arif Arin

Theses and Dissertations

In this work goal programming is used to solve a minimum cost multicommodity network flow problem with multiple goals. A single telecommunication network with multiple commodities (e.g., voice, video, data, etc.) flowing over it is analyzed. This network consists of: linear objective function, linear cost arcs, fixed capacities, specific origin-destination pairs for each commodity. A multicommodity network flow problem with goals can be successfully modeled using linear goal programming techniques. When properly modeled, network flow techniques may be employed to exploit the pure network structure of a multicommodity network flow problem with goals. Lagrangian relaxation captures the essence of the …

A Compact Ozone Differential Absorption Lidar (Dial) Transmitter Using A Solid-State Dye Polymer, Alton L. Jones Jr.

Electrical & Computer Engineering Theses & Dissertations

The measurement of atmospheric ozone is important because in the troposphere it is a pollutant that is toxic to living systems, but in the stratosphere ozone protects life by shielding us from the sun's harmful UV-B radiation.

Laser remote sensing from aircraft using differential absorption lidar (DIAL) has become a very important technique for measuring atmospheric ozone at different altitudes and locations. Current aircraft-based DIAL systems use pulsed Nd:YAG pumped liquid dye lasers, which are then frequency doubled into the UV region, to probe both the stratosphere and troposphere for ozone.

This thesis describes a new potential DIAL laser transmitter …

Inversion And Analysis Of Remotely Sensed Atmospheric Water Vapor Measurements At 940nm, Jack Cutler Larsen

Mechanical & Aerospace Engineering Theses & Dissertations

The understanding and acceptance of remotely sensed atmospheric data depends strongly on the steps taken to characterize experiment error and validate observations through comparisons to other independent measurements. A formal error analysis of the Stratospheric Aerosol and Gas Experiment II (SAGE II) water vapor operational inversion algorithm is performed and compared to previous results. Random measurement errors were characterized by segmented least-squares profile fitting of the slant path absorption which found the error to be uncorrelated in the stratosphere with estimated variances significantly smaller than expected from 18-30 km. Estimates of null space error were developed from radiosonde hygrometers in …

Manipulation Of High Spatial Resolution Aircraft Remote Sensing Data For Use In Site-Specific Farming, Gabriel B. Senay, Andrew D. Ward, John G. Lyon, Norman R. Fausey, Sue E. Nokes

Biosystems and Agricultural Engineering Faculty Publications

Three spatial data sets consisting of high spatial resolution (1 m) remote sensing images acquired in 12 spectral bands, an on-the-go yield map, and a Digital Elevation Model were co-registered and evaluated for spatial variability studies in a Geographic Information Systems environment. Separate on-the-go yield maps were developed for 3, 5, and 12 statistically significant mean yield classes. For each yield class, the corresponding mean spectral and elevation data were extracted. The relationship between mean spectral and yield data was strongly linear (r = 0.99). Also, a strong linear relationship between mean yield and elevation data (r = 0.92) was …

Development Of A Photon Counting System For Ozone Differential Absorption Lidar Signal Detection, Bradley Allen Eccles

Electrical & Computer Engineering Theses & Dissertations

A photon counting system was assembled and integrated into an existing ozone differential absorption lidar signal detection system to improve the range of ozone measurement. Results of data extraction from decaying ozone return signals are presented. Photomultiplier tube detector models EMI 9214Q and EMI 9B17Q are evaluated and characterized. Detector operating performance was based on tube quantum efficiency, gain, dark current, and linearity. The influence of photomultiplier tube characteristics on photon counting performance are discussed along with the recommended optimum photon counting operating conditions. Two photomultiplier gating schemes, focus grid and four dynode gating, are described for use in photon …

A Total Systems Analysis Method For The Conceptual Design Of Spacecraft: An Application To Remote Sensing Imager Systems, Knut I. Oxnevad

Engineering Management & Systems Engineering Theses & Dissertations

Increased emphasis is being placed on improving the performance of space projects, within tighter budgets and shorter development times. This has led to a need for more efficient space system design methods. The research described here represents an effort to develop and evaluate such a method.

Systems engineering and concurrent engineering together provide the theoretical foundation for the method. The method, derived from both this theoretical foundation and ideas from experts in the space industry, emphasizes a total systems analysis approach, taking into account given mission requirements, and the mathematical modeling of interactions between system variables and between subsystems. The …

Integrated Control Of Thermally Distorted Large Space Antennas, Robert H. Tolson

Mechanical & Aerospace Engineering Theses & Dissertations

Studies on controlling the thermal distortion of large space antennae have generally investigated a single orbital position and have optimized actuator locations based on minimizing the RMS surface deviation from the original parabolic shape. One study showed the benefits of directly using far zone electric field characteristics as the performance measure; but, this approach resulted in a nonlinear programming problem. The objective of the current study is to develop an approach to designing a control system that (1) recognizes the time dependence of the distortion and (2) controls variables that are directly related to far field performance in a quadratic …

Wind Streamline Ambiguity Removal Of Microwave Scatterometer Data, Hans W. Zaepfel

Electrical & Computer Engineering Theses & Dissertations

There is a class of satellite microwave scatterometers that return oceanographic information which includes wind vectors with directional ambiguity. The first part of the ambiguity removal process is to reduce the data to a directional ambiguity of 180°. This thesis shows that wind direction change contains the information required for streamline ambiguity removal and that syntactic pattern recognition techniques can be used to locate the areas of wind direction change. Spreading the information along the areas of wind direction change results in the removal of the streamline ambiguity. The algorithm is implemented and the results are presented showing that it …

Usage And Limitations Of Characteristic Vector Analysis Of Remote Sensing Multispectral Data For The Identification And Quantification Of Water Quality Parameters, Theodore A. Talay

Civil & Environmental Engineering Theses & Dissertations

Recent applications of the technique of characteristic vector analysis to remote-sensing water color data has met with varying degrees of success. It is apparent from these experiments that a more thorough understanding of the informational capability of characteristic vector analysis is needed.

The Development Of A Stepped Frequency Microwave Radiometer And Its Application To Remote Sensing Of The Earth, Richard Forrest Harrington

Electrical & Computer Engineering Theses & Dissertations

The design, development, application, and capabilities of a variable frequency microwave radiometer are described. This radiometer has demonstrated the versatility, accuracy, and stability required to provide contributions to the geophysical understanding of ocean and ice processes. The design technique utilized a closed-loop feedback method, whereby noise pulses were added to the received electromagnetic radiation to achieve a null balance in a Dicke switched radiometer. Stability was achieved through the use of a constant temperature enclosure around the low loss microwave front end. The Dicke reference temperature was maintained to an absolute accuracy of 0.1 K using a closed-loop proportional temperature …