Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Engineering
Absolute Positioning Using The Earth's Magnetic Anomaly Field, Aaron J. Canciani
Absolute Positioning Using The Earth's Magnetic Anomaly Field, Aaron J. Canciani
Theses and Dissertations
Achieving worldwide alternatives to GPS is a challenging engineering problem. Current GPS alternatives often suffer from limitations such as where and when the systems can operate. Navigation using the Earth's magnetic anomaly field, which is globally available at all times, shows promise to overcome many of these limitations. We present a navigation filter which uses the Earth's magnetic anomaly field as a navigation signal to aid an inertial navigation system (INS) in an aircraft. The filter utilizes highly-accurate optically pumped cesium (OPC) magnetometers to make scalar measurements of the Earth's magnetic field and compare them to a map using a …
Utilization Of A Geodesic Sphere And Quadcopter As Two-Way Field Probe For Electro-Magnetic Field Measurements In An Indoor Radar Cross Section Range, Nathan Lett
Theses and Dissertations
Radar Cross Section (RCS) measurements rely heavily on multiple assumptions. Uncertainty in the final measurement is determined based on these assumptions. One source in particular is the non-homogeneous nature of the transmission path between radar test equipment and a target under test. The following research extends prior research. This thesis intends to provide a unique two-way field probe solution for measuring Electro-magnetic (EM) fluctuations in a test volume. In this thesis, the design, development, and demonstration of a geodesic sphere encased quadcopter two-way probe is explained. The Parrot® Bebop Drone quadcopter was used with a 2v frequency divided geodesic sphere …
Using Phase Screens To Synthesize Electromagnetic Gaussian-Schell Model Sources With Desired Amplitude, Coherence, And Polarization, Christopher K. Kokoczka
Using Phase Screens To Synthesize Electromagnetic Gaussian-Schell Model Sources With Desired Amplitude, Coherence, And Polarization, Christopher K. Kokoczka
Theses and Dissertations
An electromagnetic Gaussian-Schell model (EGSM) source is built with desired coherence, amplitude, and polarization using correlated phase screens based on re- search conducted in Refs. [2, 9]. A new method of amplitude control is presented and tested using spatial light modulators (SLM). A brief review of theory and concepts is discussed followed by methods of how to build an EGSM source, correlated phase screens, and control amplitude using SLM gratings. The experimental set-up is presented which builds EGSM sources that demonstrate desired amplitude, coherence, and polarization. Irradiance correlation, degree of polarization, and Stokes parameters S0 and S1 are …
Automated Sunspot Classification And Tracking Using Sdo/Hmi Imagery, Maclane A. Townsend
Automated Sunspot Classification And Tracking Using Sdo/Hmi Imagery, Maclane A. Townsend
Theses and Dissertations
Verification of an automated sunspot detection and classification algorithm is conducted utilizing two years of solar imagery from NASA's Solar Dynamics Observatory (SDO) satellite. Automated McIntosh classifications are compared against sunspot reports from the National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center (SWPC) using a three-tiered comparison metric. Statistical confidence is demonstrated for algorithm performance and consistency when compared against the SWPC data set, suggesting future applications of the algorithm will perform similarly. A sunspot tracking algorithm is added to the existing code and demonstrates reliable feature tracking for time periods out to four days between consecutive images. …