Date of Award
2026
Document Type
Open Access Dissertation
Degree Name
Doctor of Philosophy in Electrical Engineering (PhD)
Administrative Home Department
Department of Electrical and Computer Engineering
Advisor 1
Christopher Middlebrook
Committee Member 1
Durdu Guney
Committee Member 2
Paul Bergstrom
Committee Member 3
Smitha Rao Hatti
Abstract
The increasing demand for compact, low-power, and distributed wireless sensing systems has motivated the exploration of alternative antenna technologies that overcome the limitations of conventional radio-frequency (RF) architectures. Traditional antenna systems rely on active front-end electronics, which introduce significant constraints in size, weight, power consumption, and electromagnetic interference susceptibility. These challenges are particularly pronounced in emerging applications, such as unmanned systems, distributed sensor networks, and lightweight communication platforms. This dissertation investigates electro-optic (EO) antennas as a passive alternative, enabling direct conversion of incident electromagnetic fields into optical signals for remote processing.
Electro-optic modulation techniques, including Mach–Zehnder interferometer (MZI) and ring resonator modulator (RRM) configurations, are analyzed for their suitability in antenna-integrated sensing applications. Further, a new multi RRM modulation scheme is presented and compared to MZI and RRM modulation.
The fabrication of EO antenna devices is a central focus of this work. Processes including EO polymer preparation, mixing, spin-coating, and poling are developed to create functional optical waveguides. Challenges related to film uniformity, material adhesion, and long-term stability are addressed. Material characterization is performed to evaluate optical and electrical properties critical to device performance. Measurements of refractive index, electro-optic coefficients, and dielectric properties are conducted, along with assessments of temporal stability. MZI-based devices are used to quantify modulation efficiency and sensitivity, providing key insights for design optimization.
Device design is explored at both component and system levels. Electrode structures are optimized to enhance interaction between incident RF fields and the EO material while minimizing losses. Patch antenna integration is achieved through co-design of the RF and optical elements, enabling conversion of received signals into the optical domain. Both MZI and RRM architectures are implemented and compared.
Experimental validation demonstrates the functionality of the EO antenna concept. Single-mode operation and coupling efficiency are verified through optical testing, while RF measurements confirm device response to incident electromagnetic fields. A 1×2 EO antenna array is demonstrated, enabling phase-sensitive measurements and AOA estimation. Extracted phase information is shown to correspond with expected array behavior, thus validating the preservation of phase in the optical domain. Comparisons with prior EO antenna implementations indicate improvements in optical power distribution and system performance.
This work establishes EO antennas as a viable passive alternative to conventional RF front-end architectures. Eliminating the need for active electronics at the antenna site, EO antennas enable lightweight, scalable, and electromagnetically robust sensing systems suitable for next-generation wireless applications.
Recommended Citation
Maurer, Michael A., "DESIGN OF ELECTRO OPTIC ANTENNAS AND CHARACTERIZATION OF ACTIVE ELECTRO OPTIC POLYMERS", Open Access Dissertation, Michigan Technological University, 2026.
https://digitalcommons.mtu.edu/etdr/2202