Efficient Super-Ultra-Wideband Monopole Antenna Design For Multi-Band Wireless Applications,
2024
The British University in Egypt
Efficient Super-Ultra-Wideband Monopole Antenna Design For Multi-Band Wireless Applications, Hassan Ali Ragheb, Mariam Housam, Mostafa Salah, Angie El-Damak
Electrical Engineering
The paper describes the design of a novel super ultra-wide band antenna based on frequency independent structure and defected ground plane principles. The antenna is intended to be used for applications in WLAN, WI-MAX, S band, C band, X band, K band, and 5G mm Wave frequencies. Its compact size of 55× 40 × 1.6mm3 and utilization of FR-4 substrate, offers cost-effective manufacturing. The partial ground plane configuration enhances the antenna's bandwidth. The designed antenna was fabricated and tested where the results for S11 and VSWR were compared with those obtained from the simulation. An excellent agreement was observed between …
A Comprehensive Exploration Of Fundamental And Experimental Characteristics Of Nanophotonic Metasurfaces,
2024
University of Texas at Arlington
A Comprehensive Exploration Of Fundamental And Experimental Characteristics Of Nanophotonic Metasurfaces, Nasrin Razmjooei
Electrical Engineering Dissertations - Archive
The advent of diffraction gratings with periodic unit cells has led to numerous advancements in theoretical studies and practical applications. Recently, these structures have been recognized as subsets of “meta-surfaces” or “meta-materials”, employing periodically aligned features at the wavelength scale to manipulate electromagnetic wave properties for diverse applications. This manipulation extends to controlling amplitude, phase, spectral distribution, polarization state, and the local mode structure of light across various spectral expressions. A significant characteristic of these metasurfaces is their ability to couple incident light to laterally propagating leaky Bloch modes in the subwavelength regime, resulting in resonance at specific wavelengths known …
All-Optical Signal Processing With Fiber-Based Parametric Wavelength Converters,
2024
University of Texas at Arlington
All-Optical Signal Processing With Fiber-Based Parametric Wavelength Converters, Cheng Guo
Electrical Engineering Dissertations - Archive
The optical signal degradation by optical amplifier noise set the fundamental limit of link reach in the fiber-optics networks. The industrial solution is to use the optical-electrical-optical (OEO) regenerator to clean up the noise at the expense of high-speed electronics and extra cost of laser and photodetectors. All-optical signal processing, enabled by nonlinear optics and optical fiber, intrinsically provides 2-order of magnitude higher processing bandwidth and seamless interface to fiber communication channels. However, there is no robust phase-preserving regenerator that has been experimentally demonstrated without sophisticated polarization tuning and without instable interferometric structure. In this project, we explore the applications …
Intelligent Millimeter-Wave System For Human Activity Monitoring For Telemedicine,
2024
University of Dayton
Intelligent Millimeter-Wave System For Human Activity Monitoring For Telemedicine, Abdullah K. Alhazmi, Mubarak A. Alanazi, Awwad H. Alshehry, Saleh M. Alshahry, Jennifer Jaszek, Cameron Djukic, Anna Brown, Kurt Jackson, Vamsy P. Chodavarapu
Electrical and Computer Engineering Faculty Publications
Telemedicine has the potential to improve access and delivery of healthcare to diverse and aging populations. Recent advances in technology allow for remote monitoring of physiological measures such as heart rate, oxygen saturation, blood glucose, and blood pressure. However, the ability to accurately detect falls and monitor physical activity remotely without invading privacy or remembering to wear a costly device remains an ongoing concern. Our proposed system utilizes a millimeter-wave (mmwave) radar sensor (IWR6843ISK-ODS) connected to an NVIDIA Jetson Nano board for continuous monitoring of human activity. We developed a PointNet neural network for real-time human activity monitoring that can …
Exponential Fusion Of Interpolated Frames Network (Efif-Net): Advancing Multi-Frame Image Super-Resolution With Convolutional Neural Networks,
2024
University of Dayton
Exponential Fusion Of Interpolated Frames Network (Efif-Net): Advancing Multi-Frame Image Super-Resolution With Convolutional Neural Networks, Hamed Elwarfalli, Dylan Flaute, Russell C. Hardie
Electrical and Computer Engineering Faculty Publications
Convolutional neural networks (CNNs) have become instrumental in advancing multi-frame image super-resolution (SR), a technique that merges multiple low-resolution images of the same scene into a high-resolution image. In this paper, a novel deep learning multi-frame SR algorithm is introduced. The proposed CNN model, named Exponential Fusion of Interpolated Frames Network (EFIF-Net), seamlessly integrates fusion and restoration within an end-to-end network. Key features of the new EFIF-Net include a custom exponentially weighted fusion (EWF) layer for image fusion and a modification of the Residual Channel Attention Network for restoration to deblur the fused image. Input frames are registered with subpixel …
Nano-Patterned Si Structures For Optical Filters And Electro-Mechanical Relays: Fabrication, Characterization, Prospects, And Limitations,
2024
Virginia Commonwealth University
Nano-Patterned Si Structures For Optical Filters And Electro-Mechanical Relays: Fabrication, Characterization, Prospects, And Limitations, Md Ataul Mamun
Theses and Dissertations
Nanofabrication technology, especially nanopatterning, is a rapidly advancing field that has already resulted in creating novel devices and holds promise for producing even more with unmatched performance. These techniques also allow us to gain insight into physical phenomena at the micro- and nanoscale. The ultimate performance of nanofabricated devices and their compatibility with existing Si-based CMOS technology hinge upon the careful selection of materials and precise design, coordinated with meticulous pattern transfer. In this work, we applied nanopatterning techniques on silicon to create optical filters for the shortwave infrared (SWIR) region and nanoelectromechanical system (NEMS) relay-based logic gates. Additionally, these …
Spin Wave Devices For Embedded Applications And Information Processing,
2024
Virginia Commonwealth University
Spin Wave Devices For Embedded Applications And Information Processing, Raisa Fabiha
Theses and Dissertations
Device miniaturization is a prerequisite for modern day electronics. Spintronics offers immense potential in energy efficient data storage, solid states devices, ultrafast computing and other electronic applications because of their low power consumption, non-volatile nature and unique activation mechanism. The conventional nano-antennas used for wireless communication, biomedical and wearable devices and IoT applications are limited by the traditional Harrington limit. As we attempt to miniaturize the antenna size beyond its emitted wavelength (also called “subwavelength” antenna), its gain and efficiency plummet. To overcome this challenge, the researchers have proposed magnetoelectric antennas. The ultra-thin film based magnetoelastic antennas suffer from eddy …
Photoluminescence Switching In Quantum Dots Connected With Fluorinated And Hydrogenated Photochromic Molecules,
2024
University of Virginia
Photoluminescence Switching In Quantum Dots Connected With Fluorinated And Hydrogenated Photochromic Molecules, Ephraiem S. Sarabamoun, Jonathan M. Bietsch, Pramod Aryal, Amelia G. Reid, Maurice Curran, Grayson Johnson, Esther H. R. Tsai, Charles W. Machan, Guijun Wang, Joshua J. Choi
Chemistry & Biochemistry Faculty Publications
We investigate switching of photoluminescence (PL) from PbS quantum dots (QDs) crosslinked with two different types of photochromic diarylethene molecules, 4,4'-(1-cyclopentene-1,2-diyl)bis[5-methyl-2-thiophenecarboxylic acid] (1H) and 4,4'-(1-perfluorocyclopentene-1,2-diyl)bis[5-methyl-2-thiophenecarboxylic acid] (2F). Our results show that the QDs crosslinked with the hydrogenated molecule (1H) exhibit a greater amount of switching in photoluminescence intensity compared to QDs crosslinked with the fluorinated molecule (2F). With a combination of differential pulse voltammetry and density functional theory, we attribute the different amount of PL switching to the different energy levels between 1H and 2F molecules which result in different potential barrier …
Gas Assisted Electron Beam Patterning Processes,
2024
University of Kentucky
Gas Assisted Electron Beam Patterning Processes, Deepak Kumar
Theses and Dissertations--Electrical and Computer Engineering
Radiolysis is a complex phenomenon in which molecules subjected to ionizing radiation form new chemical species. Electron-beam irradiation has proven to be a versatile approach for significantly altering materials’ properties and forms the basis for electron-beam lithography using both organic and inorganic resists. Electron-beam exposure is normally carried out under high vacuum conditions to reduce contamination and allow for unhindered interaction between the electrons and the resist material. Exposure under an ambient gas at sub-atmospheric pressures has been found to provide a distinct mechanism which can be exploited to circumvent some of the challenges associated with material processing and significantly …
Reinventing Integrated Photonic Devices And Circuits For High Performance Communication And Computing Applications,
2024
University of Kentucky
Reinventing Integrated Photonic Devices And Circuits For High Performance Communication And Computing Applications, Venkata Sai Praneeth Karempudi
Theses and Dissertations--Electrical and Computer Engineering
The long-standing technological pillars for computing systems evolution, namely Moore's law and Von Neumann architecture, are breaking down under the pressure of meeting the capacity and energy efficiency demands of computing and communication architectures that are designed to process modern data-centric applications related to Artificial Intelligence (AI), Big Data, and Internet-of-Things (IoT). In response, both industry and academia have turned to 'more-than-Moore' technologies for realizing hardware architectures for communication and computing. Fortunately, Silicon Photonics (SiPh) has emerged as one highly promising ‘more-than-Moore’ technology. Recent progress has enabled SiPh-based interconnects to outperform traditional electrical interconnects, offering advantages like high bandwidth density, …
Semiconductor Photonic Crystal Surface Emitting Lasers For High Power, High Brightness And High Speed Applications,
2024
University of Texas at Arlington
Semiconductor Photonic Crystal Surface Emitting Lasers For High Power, High Brightness And High Speed Applications, Chhabindra Gautam
Electrical Engineering Dissertations - Archive
Photonic Crystal Surface Emitting Laser (PCSEL) is the promising third generation semiconductor laser technology as it addresses the challenges of the conventional semiconductor lasers (EEL/VCSEL) by providing single mode high power output with good beam quality (thus high brightness). The large area in plane coupling resulting from the multiple Bragg’s diffraction conditions in the periodic 2D photonic crystal cavities in the lasing cladding region leads to single mode operation over very large area. By model design engineering, such in plane lasing cavity can leak the light out of the plane, which result in surface emission. The ability to scale the …
Analysis And Design Of Multiport Converters For Photovoltaic And Electrical Vehicle Applications,
2024
University of Central Florida
Analysis And Design Of Multiport Converters For Photovoltaic And Electrical Vehicle Applications, Reza Rezaii
Graduate Thesis and Dissertation 2023-2024
The widespread adoption of photovoltaic (PV) and electric vehicle (EV) technologies is crucial for mitigating greenhouse gas emissions. A Multi-Port Converter (MPC) connects multiple PV panels, improving efficiency and reducing costs. In EVs, MPCs extend battery lifespan by adding energy sources, enhancing system quality beyond reliance on Li-ion batteries. This dissertation proposes a Quad-input LLC topology for PV microinverters. It utilizes a single LLC resonant tank and two Y switches configurations. An MPPT control strategy based on Perturb and Observe (P&O) method ensures independent MPPT for each panel. The zero-voltage switching (ZVS) is achieved across all switches for wide input …
Enabling Hybrid Optical-Microwave Space Communications With Optically Transparent Rf Components Using Indium Tin Oxide (Ito),
2024
Embry-Riddle Aeronautical University
Enabling Hybrid Optical-Microwave Space Communications With Optically Transparent Rf Components Using Indium Tin Oxide (Ito), John T. O'Keefe
Doctoral Dissertations and Master's Theses
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. …
Electronic On Planes: Security Measures And Avionics Disruption,
2024
VSB-Technical University of Ostrava, Faculty of Mechanical Engineering, Insitute of Transport
Electronic On Planes: Security Measures And Avionics Disruption, Martin Jasek, Ivana Olivková
International Journal of Aviation, Aeronautics, and Aerospace
Airlines have implemented various security measures to address the use of electronics on aircraft, focusing on telecommunication services, Bluetooth technology, and personal electronic devices (PEDs). This study evaluates 50 airlines using data from websites and safety videos to assess these technologies. While the integration of new technologies like in-flight Wi-Fi and Bluetooth offers passenger benefits, concerns persist about the potential electromagnetic interference with aircraft avionics. Early research by NASA and the FCC highlighted the risks, finding that devices like mobile phones could disrupt GPS signals during critical flight phases. Despite conflicting studies, ongoing monitoring is essential to balance passenger connectivity …
Design Of Experiment Analysis On Multiple Pim Sources In An Rf Antenna System,
2024
Missouri University of Science and Technology
Design Of Experiment Analysis On Multiple Pim Sources In An Rf Antenna System, Shengxuan Xia, Yuchu He, Haicheng Zhou, Hanfeng Wang, Chulsoon Hwang
Electrical and Computer Engineering Faculty Research & Creative Works
Passive intermodulation (PIM) has been identified as one of the common root causes for receiving sensitivity degradation (desense) on radiofrequency (RF) antennas working in frequency-division duplex mode. The component-level PIM characterization and simulation have been well-established over the years. However, the study has been using an ideal 50 Ω transmission line system while antenna modules are more complicated than a simple transmission line structure. Moreover, the metallic contacts can exist in multiple locations with different connection topologies in real applications. This paper provides a method to simulate the PIM performance caused by the metallic contacts in a practical environment. In …
Ring Resonators Intergrating With Dichoric Materials And In Spin-Valley Controlled Photonic Topological System,
2024
CUNY City College
Ring Resonators Intergrating With Dichoric Materials And In Spin-Valley Controlled Photonic Topological System, Yuma Kawaguchi
Dissertations and Theses
Photonic technology plays an important role in the development of diverse applications, ranging from optical telecommunications to sensing and imaging. The utilization of photonic circuits emerges as a promising platform for the establishment of advanced communication systems characterized by high speed and large capacity. This advancement is crucial to facilitate fast and efficient data transfer while concurrently managing multiple devices. It is imperative that essential components such as lasers, modulators, and isolators exhibit compactness without incurring significant losses.
Non-reciprocal devices represent a valuable addition to photonic circuits, enabling the creation of unidirectional waveguides that function as optical isolators, preventing signals …
Hyperspectral And Polarimetric Imaging Of The Ocean For The Characterization Of The Surface Effects And Measurement Uncertainties,
2024
CUNY City College
Hyperspectral And Polarimetric Imaging Of The Ocean For The Characterization Of The Surface Effects And Measurement Uncertainties, Mateusz Malinowski
Dissertations and Theses
Ocean and coastal waters are monitored by Ocean Color satellite sensors to determine concentrations of chlorophyll and water properties and identify areas of algal blooms and other events. The light radiance from the ocean is weak in comparison with the sky radiance, which requires very accurate atmospheric correction of the radiance measured at the top of the atmosphere (TOA) on the satellite and heavy validation of the derived water leaving radiance by field measurements from the ships and ocean platforms. For TOA and especially above water radiance the skylight reflected from the ocean surface represents one of the main sources …
Hybrid Design Approaches For Reconfigurable Em Structures,
2024
Virginia Commonwealth University
Hybrid Design Approaches For Reconfigurable Em Structures, Jonathan D. Lundquist
Theses and Dissertations
The modern world is replete with reasons for employing reconfigurable electromagnetic (EM) structures, but some of the most pressing needs require advancements in power consumption, speed, and footprint [1]. Next generation air defense (NGAD) fighters could benefit from new electronic warfare (EW) countermeasures [2], as well as adaptive stealth technology [3], while doctors could benefit from reconfigurable microwave ablation antennas that can modify radiation pattern and input impedance to match changes in tissue during ablation and account for variations in tumor shapes [4]. The future of antennas, filters, and lenses is reconfigurable as real-world matters of life and death may …
Machine Learning Assisted Optimization For Calculation And Automated Tuning Of Antennas,
2024
Virginia Commonwealth University
Machine Learning Assisted Optimization For Calculation And Automated Tuning Of Antennas, Lauren Linkous
Theses and Dissertations
The Antenna Calculation and Autotuning Tool (AntennaCAT) software suite represents a significant advancement in the field of antenna design by automating the entire design, CAD, simulation, and optimization process compatible with several EM simulation software suites. It is the first comprehensive implementation of machine learning in this context. In particular, this work includes the capability to create and export structured datasets from the aforementioned EM software for iterative improvement and includes an expandable selection of optimizers.
Bridging The Gap In Epsilon-Near-Zero Nonlinear Materials,
2024
Virginia Commonwealth University
Bridging The Gap In Epsilon-Near-Zero Nonlinear Materials, Adam R. Ball
Theses and Dissertations
Studying how light and matter interact has been of interest to humans for thousands of years. From the invention of the first mirror, burning ants with a magnifying glass, to optical fiber communication, light has been central to mankind. Researchers have sought to take this to the extreme with nonlinear optics where intense laser light interacts with materials. The study of this thesis is to understand a new generation of materials that has come to light. Epsilon-near-zero (ENZ) materials have shown promise for ultrafast light manipulation in tandem with modern day CMOS compatible electronics. Here, I seek to bridge the …
