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Air Force Institute of Technology

1999

Kalman filtering

Articles 1 - 2 of 2

Full-Text Articles in Engineering

Antenna Gain Enhancement Using A Photonic Band Gap Reflector, Karl C. Schloer Mar 1999

Antenna Gain Enhancement Using A Photonic Band Gap Reflector, Karl C. Schloer

Theses and Dissertations

Scientists have long known that periodic structures can filter electromagnetic (EM) waves. In the last decade, extension of one- and two-dimensionally periodic structures into a third periodic dimension has produced photonic band gap (PBG) structures. A PBG structure is characterized by its omnidirectional stop band at a set of frequencies determined by the structure's periodicity and permittivity. In the present research, we investigate such a structure as an antenna reflector. We aim to develop a modeling approach that provides accurate computations of PBG behavior without relying on massively parallel processing. We also construct and measure the bulk reflection and transmission …


Ultra-Wideband Tem Horns, Transient Arrays And Exponential Curves: A Fdtd Look, Troy S. Utton Mar 1999

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 …