Date of Award
Winter 2024
Access Type
Thesis - Open Access
Degree Name
Master of Science in Electrical & Computer Engineering
Department
Electrical, Computer, Software, and Systems Engineering
Committee Chair
Eduardo Rojas
First Committee Member
M. Ilhan Akbas
Second Committee Member
Bryan Watson
College Dean
James W. Gregory
Abstract
Over the last decade, spacecraft have increasingly integrated both microwave and optical communication systems, driving the need for electrically conductive and optically transparent materials. This study presents a comprehensive examination of advanced electromagnetic characterization techniques and the design, fabrication, and performance of optically transparent antennas using Indium Tin Oxide (ITO) films on alkaline earth boro-aluminosilicate glass for transparent radio-frequency (RF) applications in space communication systems. Addressing the limitations of traditional metal-based antennas—particularly their shadowing effect on satellite solar cells—this study investigates ITO as a pivotal material for creating antennas that are both efficient in communication and non-intrusive to solar efficiency. Utilizing 4-point probes and coplanar waveguide (CPW) ground signal ground (GSG) probes, we investigated the electrical properties of ITO, including conductivity, permittivity, and loss tangent, and ensured the material's suitability for space conditions and electrical conductivity. The ITO films achieved an average permittivity of 7.16 in the range of 5-10 GHz, a DC conductivity of 6.86 MS/m, and a CPW loss tangent of 0.0054 at 10 GHz. The Ansys High-Frequency Structure Simulator (HFSS) was employed for the design and optimization of these antennas, focusing on their performance in wideband frequency applications and compatibility with satellite solar cell standards. The simulated -10 dB impedance bandwidth was found to be 154\%, and the measured -10 dB impedance bandwidth was 156\%, covering a wide range from 1.4 GHz to 10.9 GHz. Additionally, the simulated peak antenna gain was observed to be 3.2 dBi at 6 GHz, indicating the antenna's effective performance over a broad frequency range. The fabrication process, utilizing the nScrypt system and a femtosecond laser, demonstrated high precision in constructing the antenna structure according to the optimized design. Our results show significant improvements in impedance bandwidth and gain, confirming the antenna's ability to operate efficiently over a wide frequency range while enhancing solar efficiency. These results underscore the suitability of ITO for hybrid optical and microwave hardware, offering critical insights into the design of next-generation electronic and photonic devices. The successful integration of this optically clear, single-layer antenna design with solar panel systems paves the way for more efficient and space-saving communication solutions in satellite technology, demonstrating the pivotal role of precise material characterization in advancing space communication technologies.
Scholarly Commons Citation
O'Keefe, John T., "Enabling Hybrid Optical-Microwave Space Communications with Optically Transparent RF Components Using Indium Tin Oxide (ITO)" (2024). Doctoral Dissertations and Master's Theses. 870.
https://commons.erau.edu/edt/870
