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Low Cross-Polarization Vivaldi Arrays, John Logan
Low Cross-Polarization Vivaldi Arrays, John Logan
Doctoral Dissertations
Ultra-wideband (UWB) electronically scanned arrays (ESA) with high efficiency, excellent polarization agility, and wide-scan matching remain essential for servicing multifunctional RF front-ends and other communications, sensing, and jamming or countermeasure systems. To this day, the most popular antenna array element in modern UWB-ESA systems is the Vivaldi, or flared notch, due to its superior wide-scan wide impedance bandwidth, well-known design guidelines, and practical embodiment versatility. Despite their popularity, these arrays tend to radiate unacceptably high cross-polarization levels, thus encouraging a great research opportunity. This dissertation presents the theory and design of a new class of UWB-ESAs, termed Sliced Notch Antenna …
A New Class Of Improved Bandwidth Planar Ultrawideband Modular Antenna (Puma) Arrays Scalable To Mm-Waves, John Logan
A New Class Of Improved Bandwidth Planar Ultrawideband Modular Antenna (Puma) Arrays Scalable To Mm-Waves, John Logan
Masters Theses 1911 - February 2014
A new class of Planar Ultrawideband Modular Antenna (PUMA) arrays, termed PUMAv3, is introduced to offer improved performance and further meet demand needs for multifunctional systems. PUMAv3 extends the frequency scalability of PUMA arrays to mm-waves (approximately 50 GHz) and improves bandwidth by 50\% without the use of a matching network or external baluns. The major enabling technical innovation is the advent of a new common-mode mitigation mechanism that relies upon capacitively-loaded shorting vias to push broadside catastrophic resonances below the operating band without inhibiting low-end bandwidth performance. Ridged waveguide models are employed to explain the operational principles and accurately …