Design, fabrication and characterization of Terahertz System-on-Chip filters
| dc.contributor.author | Dehghanian, Seyedali | |
| dc.contributor.supervisor | Smith, Levi | |
| dc.contributor.supervisor | Darcie, Thomas Edward | |
| dc.date.accessioned | 2025-08-28T21:37:08Z | |
| dc.date.available | 2025-08-28T21:37:08Z | |
| dc.date.issued | 2025 | |
| dc.degree.department | Department of Electrical and Computer Engineering | |
| dc.degree.level | Doctor of Philosophy PhD | |
| dc.description.abstract | Terahertz System-on-Chip (TSoC) technology has emerged as a compact and integrated alternative to conventional free-space Terahertz (THz) systems, addressing critical challenges such as signal propagation losses, pulse distortion, high implementation costs, and system integration complexities. Despite these advancements, a gap remains in fully exploiting the potential of TSoC platforms for the design and optimization of integrated THz filters. This work presents the design, simulation, and experimental validation of multiple integrated THz filters within the TSoC framework. Leveraging impedance-engineered Coplanar Strip (CPS) transmission lines, these filters achieve precise frequency selectivity, enabling controlled signal transmission and rejection at THz frequencies. Specifically, the investigated designs include: (i) a band-stop THz Apodized Bragg Grating (TABG), (ii) a planar multimodal periodic filter at THz frequencies, and (iii) low-pass planar all-pole network filters based on stepped-impedance Bessel designs of orders 3, 4, and 5. The fabricated filters were experimentally validated using Terahertz Time-Domain Spectroscopy (THz-TDS), demonstrating strong agreement between simulated results obtained using commercial software (ANSYS HFSS) and measured data, thereby confirming the effectiveness of the proposed designs. To further automate the design process of THz filters—particularly in scenarios where conventional methods are impractical or insufficient—this study introduces an inverse-design methodology based on a natural selection optimization technique. Leveraging the Genetic Algorithm (GA), the proposed approach systematically and efficiently explores the design space to achieve optimal filter characteristics. The flexibility of this framework enables accommodation of diverse design objectives, including varying center frequencies, rejection depths, and impedance matching requirements, making it a promising tool for next-generation TSoC components. This approach not only streamlines the filter design process but also establishes a foundation for the automated synthesis of other THz components, such as couplers, multiplexers, and power dividers. The experimental results presented in this work confirm the practical feasibility of planar filters for real-world applications. By offering valuable insights into the rapidly advancing TSoC framework, this dissertation establishes a solid foundation for the continued exploration of compact planar filters using both classical and modern design methodologies. Future research can build upon these contributions by bridging the gap between academic developments and industrial applications, and by extending the methodologies to a broader class of components, with the aim of further enhancing the performance and versatility of integrated THz technologies. | |
| dc.description.scholarlevel | Graduate | |
| dc.identifier.bibliographicCitation | A. Dehghanian, W. Gomaa, M. Haghighat, T. Darcie, and L. Smith, “Demonstration of an integrated terahertz band-stop filter using an apodized bragg grating,” Optics Express, vol. 31, no. 20, pp. 32582–32590, 2023. | |
| dc.identifier.bibliographicCitation | A. Dehghanian, M. Haghighat, T. Darcie, and L. Smith, “Demonstration of a planar multimodal periodic filter at thz frequencies,” Journal of Infrared, Millimeter, and Terahertz Waves, vol. 46, no. 6, pp. 1–17, 2025. | |
| dc.identifier.bibliographicCitation | A. Dehghanian, M. Haghighat, T. Darcie, and L. Smith, “Demonstration of a terahertz integrated planar network synthesis filter,” Optics Continuum, vol. 3, no. 1, pp. 71–77, 2024. | |
| dc.identifier.bibliographicCitation | A. Dehghanian, T. Darcie, and L. Smith, “Genetic algorithm-based inverse design of guided wave planar terahertz filters,” 2025. | |
| dc.identifier.uri | https://hdl.handle.net/1828/22680 | |
| dc.language | English | eng |
| dc.language.iso | en | |
| dc.rights | Available to the World Wide Web | |
| dc.subject | Terahertz | |
| dc.subject | Filter | |
| dc.subject | System-on_Chip | |
| dc.subject | Genetic Algorithm | |
| dc.subject | Bragg Grating | |
| dc.subject | Coplanar Strip | |
| dc.subject | Bessel | |
| dc.subject | Terahertz Time-Domain Spectroscopy | |
| dc.title | Design, fabrication and characterization of Terahertz System-on-Chip filters | |
| dc.type | Thesis |