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Full-Text Articles in Engineering
Integrated Ups/Ins Precision Approach Landing With M3ae Interference Avoidance, Stephan H. Chastain
Integrated Ups/Ins Precision Approach Landing With M3ae Interference Avoidance, Stephan H. Chastain
Theses and Dissertations
Several past research efforts have developed methods to take advantage of Global Positioning System (UPS) positioning and apply it to a precision landing system (PLS). There have been proposals to phase out the current Instrument Landing System (ILS) in favor of a more cost-efficient and effective system. Accomplishments have been made in detailing a system implementing an INS aided with differential UPS, a UPS pseudolite, and a radar altimeter to handle the critical PLS requirements. This research applies the newly developed Modified Multiple Model Adaptive Estimation (M3AE) architecture in an attempt to enhance the performance of a PLS in an …
Application Of The Finite Element Method To The Scattering Of A Two-Dimensional, Semi-Infinite Periodic Structure, Perry N. Villanueva
Application Of The Finite Element Method To The Scattering Of A Two-Dimensional, Semi-Infinite Periodic Structure, Perry N. Villanueva
Theses and Dissertations
Infinite periodic structures have been studied heavily because of their efficient filtering capabilities. They generally exhibit sharp frequency roll-offs at the frequency band of interest. In the RF region of the electromagnetic spectrum, periodic structures find applications such as radomes and photonic bandgap materials. Most studies have been done with infinitely periodic arrays because it is convenient to collapse an infinite array into one representative period using Floquet Analysis. Truncating an infinite array introduces an edge and invalidates Floquet analysis over the entire array. This thesis formulates a Finite Element Method (FEM) solution of a semi-infinite periodic array consisting of …
Ultra-Wideband Tem Horns, Transient Arrays And Exponential Curves: A Fdtd Look, Troy S. Utton
Ultra-Wideband Tem Horns, Transient Arrays And Exponential Curves: A Fdtd Look, Troy S. Utton
Theses and Dissertations
This research investigates the possibility of applying exponentially curved conducting plates to single-element Transverse Electromagnetic (TEM) horns and their transient arrays to enhance the UWB characteristics already experienced by these radiators. The first part of this study demonstrates the Finite-Difference Time-Domain (FDTD) method's ability to duplicate experimental data, and establishes the baseline models used throughout the remainder of the research. The baseline models consist of the typical flat-triangle shaped conducting plates. The exponential taper models incorporate the exponential curves in the height, the width, and both the height and width directions. One, two- and four-element baseline configurations are compared to …