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Full-Text Articles in Engineering

Geometric Analysis Of The Doppler Frequency For General Non-Stationary 3d Mobile-To-Mobile Channels Based On Prolate Spheroidal Coordinates, Michael Walter, Dmitriy Shutin, Martin Schmidhammer, David W. Matolak, Alenka Zajic Oct 2020

Geometric Analysis Of The Doppler Frequency For General Non-Stationary 3d Mobile-To-Mobile Channels Based On Prolate Spheroidal Coordinates, Michael Walter, Dmitriy Shutin, Martin Schmidhammer, David W. Matolak, Alenka Zajic

Faculty Publications

—Mobile-to-mobile channels often exhibit time-variant Doppler frequency shifts due to the movement of transmitter and receiver. An accurate description of the Doppler frequency turns out to be very difficult in Cartesian coordinates and any subsequent algebraic analysis of the Doppler frequency is intractable. In contrast to other approaches, we base our investigation on a geometric description of the Doppler frequency with the following three mathematical pillars: prolate spheroidal coordinate system, algebraic curve theory, and differential forms. The prolate spheroidal coordinate system is more appropriate to algebraically investigate the problem. After the transformation into the new coordinate system, the theory of …


Advances In High-Resolution Radiation Detection Using 4h-Sic Epitaxial Layer Devices, Krishna C. Mandal, Joshua W. Kleppinger, Sandeep K. Chaudhuri Feb 2020

Advances In High-Resolution Radiation Detection Using 4h-Sic Epitaxial Layer Devices, Krishna C. Mandal, Joshua W. Kleppinger, Sandeep K. Chaudhuri

Faculty Publications

Advances towards achieving the goal of miniature 4H-SiC based radiation detectors for harsh environment application have been studied extensively and reviewed in this article. The miniaturized devices were developed at the University of South Carolina (UofSC) on 8 × 8 mm 4H-SiC epitaxial layer wafers with an active area of ≈11 mm2. The thicknesses of the actual epitaxial layers were either 20 or 50 µm. The article reviews the investigation of defect levels in 4H-SiC epilayers and radiation detection properties of Schottky barrier devices (SBDs) fabricated in our laboratories at UofSC. Our studies led to the development of …