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Articles 481 - 510 of 1749
Full-Text Articles in Electromagnetics and Photonics
On-Chip Nonreciprocal Components For Full-Duplex Communications And Gaussian Regulated Gate Driver For Electromagnetic Interference Reduction, Chang Yang
Electrical Engineering Theses and Dissertations
This dissertation is comprised of two unrelated design endeavors. The first one is about two CMOS nonreciprocal components: 1) an isolator and 2) a circulator. To make the components compact enough for the next generation communication systems with wide bandwidth, both components operate at 100 GHz band for full-duplex transceivers for ultra-high-data-rate millimeter-wave wireless communication. The proposed nonreciprocal structures are based on a time-domain modulation by signals at around 1/6 of the RF frequencies and spatial duplexing over the RF signal paths, demonstrating over 45 dB isolation in a bandwidth of 1.5 GHz over the tuning range of 85-110 GHz. …
Systematic Power Integrity Analysis Based On Inductance Decomposition In A Multi-Layered Pcb Pdn, Biyao Zhao, Siqi Bai, Samuel Connor, Stephen Scearce, Matteo Cocchini, Brice Achkir, Albert E. Ruehli, Bruce Archambeault, Jun Fan, James L. Drewniak
Systematic Power Integrity Analysis Based On Inductance Decomposition In A Multi-Layered Pcb Pdn, Biyao Zhao, Siqi Bai, Samuel Connor, Stephen Scearce, Matteo Cocchini, Brice Achkir, Albert E. Ruehli, Bruce Archambeault, Jun Fan, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
An approach is presented for power integrity analysis on multi-layer printed circuit boards in this paper. Two critical current paths are analyzed. Inductance decomposition is applied to identify the critical parameters that can influence the PDN input impedance. Two types of stack-ups are used to perform sensitivity analysis to illustrate the effectiveness of PDN design guidelines. Based on the analysis of the inductance contribution from different blocks in the PCB PDN, a systematic approach to obtain a complete understanding of PDN behavior is proposed. The approach can be used to provide design guidance in PDN design practice.
Artificial Neural Network Discovery Of A Switchable Metasurface Reflector, J. R. Thompson, J. A. Burrow, P. J. Shah, J. Slagle, E. S. Harper, A. Van Rynbach, I. Agha, M. S. Mills
Artificial Neural Network Discovery Of A Switchable Metasurface Reflector, J. R. Thompson, J. A. Burrow, P. J. Shah, J. Slagle, E. S. Harper, A. Van Rynbach, I. Agha, M. S. Mills
Electro-Optics and Photonics Faculty Publications
Optical materials engineered to dynamically and selectively manipulate electromag- netic waves are essential to the future of modern optical systems. In this paper, we simulate various metasurface configurations consisting of periodic 1D bars or 2D pillars made of the ternary phase change material Ge2Sb2Te5 (GST). Dynamic switching behavior in reflectance is exploited due to a drastic refractive index change between the crystalline and amorphous states of GST. Selectivity in the reflection and transmission spectra is manipulated by tailoring the geometrical parameters of the metasurface. Due to the immense number of possible metasurface configurations, we train deep neural networks capable of …
A Brief Bibliometric Survey On Circularly Polarized Antennas For Mobile Communication, Aniket Gunjal, Abhaya Pal Singh
A Brief Bibliometric Survey On Circularly Polarized Antennas For Mobile Communication, Aniket Gunjal, Abhaya Pal Singh
Library Philosophy and Practice (e-journal)
This paper presents a database review on “Circularly Polarized Antennas for Mobile Communication” as it is the emerging technique used by mobile service provider because of having benefits over other types of antennas available.The polarization purity is now the major issue. In some cases due to cross polarization issue the antenna signal is cancelled at receiver side.So, it is necessary to have circularly polarized antenna to avoid this polarization issue because of change in phase of signal. The change in phase of signal is due to striking of wave on the obstacles and it slightly tilted from its direction causes …
Validation Of Nanosecond Pulse Cancellation Using A Quadrupole Exposure System, Hollie A. Ryan
Validation Of Nanosecond Pulse Cancellation Using A Quadrupole Exposure System, Hollie A. Ryan
Biomedical Engineering Theses & Dissertations
Nanosecond pulsed electric fields (nsPEFs) offer a plethora of opportunities for developing integrative technologies as complements or alternatives to traditional medicine. Studies on the biological effects of nsPEFs in vitro and in vivo have revealed unique characteristics that suggest the potential for minimized risk of complications in patients, such as the ability of unipolar nsEPs to create permanent or transient pores in cell membranes that trigger localized lethal or non-lethal outcomes without consequential heating. A more recent finding was that such responses could be diminished by applying a bipolar pulse instead, a phenomenon dubbed bipolar cancellation, paving the way …
Calibration Loop Antenna For Multiple Probe Antenna Measurement System, Yuming Zheng, Zibin Weng, Yihong Qi, Jun Fan, Fuhai Li, Zhiping Yang, James L. Drewniak
Calibration Loop Antenna For Multiple Probe Antenna Measurement System, Yuming Zheng, Zibin Weng, Yihong Qi, Jun Fan, Fuhai Li, Zhiping Yang, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
In order to achieve high accuracy in measurements of the multiple probe antenna measurement system (MPAMS), an omnidirectional calibration antenna with a small gain variation in the horizontal polarization (named calibration loop antenna, in convention) is required. This article presents such an antenna design. The proposed calibration loop antenna consists of four arc-folded dipoles with dimensions of 52 mm x52 mm x 1 mm, balun structures for suppressing common mode current, and four parasitic strips for impedance matching on each of the top and bottom planes. The experimental results show that the proposed calibration loop antenna has a small gain …
Total Isotropic Sensitivity Measurement In Switched Beam Antenna Systems, Jun Li, Yihong Qi, Wei Yu, Fuhai Li, Jun Fan, Zhiping Yang, Songping Wu, James L. Drewniak
Total Isotropic Sensitivity Measurement In Switched Beam Antenna Systems, Jun Li, Yihong Qi, Wei Yu, Fuhai Li, Jun Fan, Zhiping Yang, Songping Wu, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
Smart antenna systems (SAS) play an important role in wireless communication systems, especially in rapidly developing fifth generation (5G) systems. In normal device under test (DUT) applications with SAS, the antenna's state may change in different external environments in order to obtain higher antenna gains and better connection with the base station, resulting in high uncertainties for over-the-air (OTA) tests using conventional methods. Before evaluating the transceiver performance, additional application programs are necessary to control the DUT, which increases the inconvenience for engineers and makes it impossible to reflect the real usage scenario. This article proposes a new convenient method …
Physics-Based Circuit Modeling Methodology For System Power Integrity Analysis And Design, Biyao Zhao, Siqi Bai, Samuel Connor, Wiren Dale Becker, Matteo Cocchini, Jonghyun Cho, Albert E. Ruehli, Bruce Archambeault, James L. Drewniak
Physics-Based Circuit Modeling Methodology For System Power Integrity Analysis And Design, Biyao Zhao, Siqi Bai, Samuel Connor, Wiren Dale Becker, Matteo Cocchini, Jonghyun Cho, Albert E. Ruehli, Bruce Archambeault, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
A physics-based circuit modeling methodology for system-level power integrity (PI) analysis and design is presented herein. The modeling methodology is based on representing the current paths in the power distribution network (PDN) with appropriate circuits based on cavity model and plane-pair partial element equivalent circuit (PEEC). The PDN input impedance looking from on-chip sources can be computed. A commercial simulation tool is used to corroborate the modeling approach where the system consists of a commercial integrated circuit, a complex organic package and a very high-layer-count printed circuit board. Two types of circuit models are proposed from the methodology with physical …
Development Of Bragg Fiber Sensor For Corrosion Detection, Cai Hui Tan
Development Of Bragg Fiber Sensor For Corrosion Detection, Cai Hui Tan
Student Works (2020-2029)
Steel corrosion has posed one of the major structural defects in the civil society today. Conventional methods for corrosion monitoring involve high maintenance cost and destructive methods with low accuracy. Recently, Fiber Bragg gratings (FBG) sensor with its high sensitivity in measuring strain and temperature have been widely studied and used in structural health monitoring (SHM). A non-destructive corrosion detection approach based on FBG sensors was developed and tested to monitor corrosion in this research work. The principle of FBG sensing is based on Bragg wavelength shifts that from the corrosion process that induced strain on the FBG due to …
Organic Materials As Saturable Absorber For Pulse Generation At Telecommunication Window, Mohammed Hussein Sameer Salam M.H.
Organic Materials As Saturable Absorber For Pulse Generation At Telecommunication Window, Mohammed Hussein Sameer Salam M.H.
Student Works (2020-2029)
This thesis demonstrates several types of fiber lasers based on newly developed organic materials as saturable absorbers (SAs). We used these SAs in all-fiber based erbium-doped fiber laser (EDFL) ring cavity to produce Q-switched and mode-locked pulses at telecommunication window, at ~ 1560 nm. Three different organic materials were used in this thesis: Bis[2-(4,6-difluorophenyl)pyridinato-C2 ,N](picolinato)iridium(III) (FIrpic), bis(8-hydroxyquinoline)zinc (Znq2) and Tris(8-hydroxyquinoline)aluminum (Alq3). Finding new materials is still one of the defining characteristics of nonlinear optics field, as the rapid development of SAs has provided several new opportunities for nonlinear optics. Throughout this work, organic material showed a very interesting performance in …
Advanced Parallel Algorithms In Computational Electromagnetics, Shu Wang
Advanced Parallel Algorithms In Computational Electromagnetics, Shu Wang
Electrical and Computer Engineering ETDs
The rapid development of high performance computing has pushed the computational electromagnetic(CEM) towards high accuracy, high fidelity and extreme computational scales. There is a great need for existing CEM solvers to have enhanced parallelism and scaling capability. The purpose of this dissertation is to investigate advanced parallel algorithms for both frequency and time domain solvers.
In frequency domain, this work first develop the underpinnings of parallel preconditioning technique and high-order transmission condition in the context of multi-solver scheme. The result is a computing resource-aware and implementation wise compact solver. Then this work targeted at developing efficient algorithms for cases where …
Nonlinear Nanophotonic Devices In The Ultraviolet To Visible Wavelength Range, Jinghan He, Hong Chen, Jin Hu, Jingan Zhou, Yingmu Zhang, Andre Kovach, Constantine Sideris, Mark C. Harrison, Yuji Zhao, Andrea M. Armani
Nonlinear Nanophotonic Devices In The Ultraviolet To Visible Wavelength Range, Jinghan He, Hong Chen, Jin Hu, Jingan Zhou, Yingmu Zhang, Andre Kovach, Constantine Sideris, Mark C. Harrison, Yuji Zhao, Andrea M. Armani
Engineering Faculty Articles and Research
Although the first lasers invented operated in the visible, the first on-chip devices were optimized for near-infrared (IR) performance driven by demand in telecommunications. However, as the applications of integrated photonics has broadened, the wavelength demand has as well, and we are now returning to the visible (Vis) and pushing into the ultraviolet (UV). This shift has required innovations in device design and in materials as well as leveraging nonlinear behavior to reach these wavelengths. This review discusses the key nonlinear phenomena that can be used as well as presents several emerging material systems and devices that have reached the …
Predicting The Conducted Emission Of A Crm Pfc Below 1mhz By Transient Modeling, Hongseok Kim, Jiayi He, Chunyu Wu, Nicholas Erickson, Sangho Cho, Dohyung Kim, Yeong Hur, Jun Fan
Predicting The Conducted Emission Of A Crm Pfc Below 1mhz By Transient Modeling, Hongseok Kim, Jiayi He, Chunyu Wu, Nicholas Erickson, Sangho Cho, Dohyung Kim, Yeong Hur, Jun Fan
Electrical and Computer Engineering Faculty Research & Creative Works
Power Factor Corrections (PFC) are widely used in ac to dc power supplies. Modeling the PFC circuits and predicting the conducted emission (CE) are important in power supply designs. This paper introduces a transient model of a critical conduction mode (CRM) power factor correction. The control circuit of the PFC is built to achieve a CRM working condition with a constant on-time switching. The simulated time domain noise waveform is converted to the conducted EMI in frequency domain via short-time fast Fourier transform (STFFT). The simulated conducted EMI is compared to measured results below 1MHz.
Investigation Of The Structural, Electronic, And Thermoelectric Properties Of Mono- Chalcogenides, Aida Sheibani
Investigation Of The Structural, Electronic, And Thermoelectric Properties Of Mono- Chalcogenides, Aida Sheibani
Graduate Theses and Dissertations
The structural, electronic, and thermoelectric properties of GeTe are studied using density functional theory and Boltzmann transport equations. This material has a rhombohedral crystal structure in ambient temperature with a ferroelectric behavior due to lack of inversion symmetry. This study suggests that the presence of asymmetry in GeTe can lead to an improvement in the thermoelectric properties of this material. In addition, studies on introducing Group III, IV, and V dopants to GeSe show that while these impurities can improve the power factor and decrease the lattice thermal conductivity, they cannot enhance the figure of merit.
Electric Parameter Tuning Of Wireless Power Transfer Coil For Charging Interoperability Of Electric Vehicles, Dongwook Kim, Seungyoung Ahn, Qiusen He, Anfeng Huang, Jun Fan, Hongseok Kim
Electric Parameter Tuning Of Wireless Power Transfer Coil For Charging Interoperability Of Electric Vehicles, Dongwook Kim, Seungyoung Ahn, Qiusen He, Anfeng Huang, Jun Fan, Hongseok Kim
Electrical and Computer Engineering Faculty Research & Creative Works
The SAE J2954 recommended practice (RP) contains the power transfer frequency, electric values, and test procedure for the electric vehicle (EV) wireless power transfer (WPT). In particular, this document expresses the inductance range of the powering coil, the power receiving coil and the coupling coefficient (k) and the impedance values. It is very important that adhering the electrical parameters in the standard considering that the wireless charging system's compatibility. However, once the coil is processed, it is not easy to adjust the inductance of each powering coil, power receiving coil as well as the coupling coefficient of between transmitting coil …
The Effect Of The Parallel-Plate Mode On Striplines In Inhomogeneous Dielectric Media, Jiayi He, Shaohui Yong, Zurab Kiguradze, Arun Chada, Bhyrav Mutnury, James Drewniak
The Effect Of The Parallel-Plate Mode On Striplines In Inhomogeneous Dielectric Media, Jiayi He, Shaohui Yong, Zurab Kiguradze, Arun Chada, Bhyrav Mutnury, James Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
Strip lines are widely used in high speed printed circuit boards (PCB). When the strip line is in inhomogeneous dielectric media, its principal operation mode is quasi-TEM. In this case, the parallel-plate mode between two ground planes can be excited as a parasitic mode. This paper investigates the effect of this parasitic mode on strip lines through simulations. The simulated S-parameters of strip lines when this parallel-plate mode is excited and suppressed are compared. The measured S-parameters of strip lines with and without the ground stitching vias are also compared. The impact of the parasitic mode on time domain crosstalk …
Low Emf Design Of Cochlear Implant Wireless Power Transfer System Using A Shielding Coil, Seokwoo Hong, Seungtaek Jeong, Seongsoo Lee, Boogyo Sim, Hongseok Kim, Joungho Kim
Low Emf Design Of Cochlear Implant Wireless Power Transfer System Using A Shielding Coil, Seokwoo Hong, Seungtaek Jeong, Seongsoo Lee, Boogyo Sim, Hongseok Kim, Joungho Kim
Electrical and Computer Engineering Faculty Research & Creative Works
Wireless power transfer (WPT) technology is widely used for various applications because of convenience and safety. Especially, medical implant devices such as a cochlear implant are one of the typical applications of the WPT technology. However, WPT systems have problems with electromagnetic field (EMF) leakage, which can cause electro-magnetic interference (EMI) issues in the human body. In this paper, we propose an additional shielding coil for the effective suppression of EMF radiation of a WPT system. The proposed method reduces the EMF leakage in operating frequency range. We verified that the proposed shielding coil reduced the EMF leakage by 5.1 …
An Enhanced Deep Reinforcement Learning Algorithm For Decoupling Capacitor Selection In Power Distribution Network Design, Ling Zhang, Wenchang Huang, Jack Juang, Hank Lin, Bin Chyi Tseng, Chulsoon Hwang
An Enhanced Deep Reinforcement Learning Algorithm For Decoupling Capacitor Selection In Power Distribution Network Design, Ling Zhang, Wenchang Huang, Jack Juang, Hank Lin, Bin Chyi Tseng, Chulsoon Hwang
Electrical and Computer Engineering Faculty Research & Creative Works
The selection of decoupling capacitors (decap) is a critical but tedious process in power distribution network (PDN) design. In this paper, an improved decap-selection algorithm based on deep reinforcement learning (DRL), which seeks the minimum number of decaps through a self-exploration training to satisfy a given target impedance, is presented. Compared with the previous relevant work: the calculation speed of PDN impedance is significantly increased by adopting an impedance matrix reduction method; also, the enhanced algorithm performs a better convergence by utilizing the techniques of double Q-learning and prioritized experience replay; furthermore, a well-designed reward is proposed to facilitate long-term …
High-Speed Channel Equalization Applying Parallel Bayesian Machine Learning, Zurab Kiguradze, Nana Dikhaminjia, Mikheil Tsiklauri, Jiayi He, Bhyrav Mutnury, Arun Chada, James L. Drewniak
High-Speed Channel Equalization Applying Parallel Bayesian Machine Learning, Zurab Kiguradze, Nana Dikhaminjia, Mikheil Tsiklauri, Jiayi He, Bhyrav Mutnury, Arun Chada, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
Recovering attenuated signals caused by different issues including connections between connectors and chips of the devices, channel loss, and crosstalk is a challenging problem. Equalization is the most popular way to restore distorted signals. Different optimization algorithms are used to find the best tap coefficients for each equalization that improves eye opening and decreases the bit error rate (BER). Nowadays algorithms of equalization mainly operate to reduce the difference between input and output signals. In turn, this will increase eye height indirectly, but direct maximization of the eye height will restore the signal even better. The paper proposes a new …
Decoupling Capacitor Power Ground Via Layout Analysis For Multi-Layered Pcb Pdns, Biyao Zhao, Shuang Liang, Samuel Connor, Matteo Cocchini, Brice Achkir, Albert E. Ruehli, Bruce Archambeault, Jun Fan, James L. Drewniak
Decoupling Capacitor Power Ground Via Layout Analysis For Multi-Layered Pcb Pdns, Biyao Zhao, Shuang Liang, Samuel Connor, Matteo Cocchini, Brice Achkir, Albert E. Ruehli, Bruce Archambeault, Jun Fan, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
A modeling methodology to calculate the decoupling capacitor interconnect inductance in a multi-layer PCB is proposed herein. The methodology is based on the resonant cavity model of parallel planes. The self-inductance and mutual inductance are extracted to understand the via configuration influence on the effectiveness of decoupling capacitors. A special layout of decoupling capacitor is proposed to increase the effectiveness of the decoupling capacitors by taking maximum advantage of the mutual inductance between interconnect vias with two decoupling capacitors placed in a pair, and two pairs of power and ground vias placed in alternating directions as close as possible. The …
Development Of High-Density Propulsion System Technologies For Interplanetary Small Satellites And Cubesats, Morgan Andrew Roddy
Development Of High-Density Propulsion System Technologies For Interplanetary Small Satellites And Cubesats, Morgan Andrew Roddy
Graduate Theses and Dissertations
The goal of this research was to support the development of a novel propulsion system for small satellites (<180 kg) and CubeSats. This was pursued by conducting a collection of studies that were designed to provide engineering data that would be critical in designing a functional prototype. The novel propulsion system was conceived by the author to provide best-in-class performance for the small satellite and CubeSat families of spacecraft. This context presents specific design requirements that the presented technology attempts to satisfy. The most critical among these is high density; the propellant was designed to be stored with high density and the thruster was designed to be as compact as possible. The propulsion system is composed of two primary elements, a propellant generator and a thruster. The propellant generator works by sublimating a solid crystal into vapor and then using this vapor to etch a dense metal. The resulting gaseous byproducts of this reaction are the propellant. This dissertation used xenon difluoride (XeF2) vapor to etch tungsten (W) which react to form xenon gas (Xe) and tungsten hexafluoride (WF6). This approach gave a theoretical propellant storage density 5.40 g/cm3; and 5.17 g/cm3 was demonstrated. The sublimation dynamics of the XeF2 were studied as a function of surface area and temperature and it was found to be suitable for the intended application due to its high effluence rate; that is, it sublimates fast enough to be useful. The sublimation rates are on the order of 10’s of µg/s. The etch rate of XeF2 on W was also studied and found to be suitably fast to provide useful amounts of reactants for use as a propellant, again on the order of 1’s of µg/s. The thruster is an electrostatic radio frequency (RF) ion thruster design and is manufactured with Low Temperature Co-Fired Ceramic (LTCC) materials system and manufacturing technology. Manufacturing samples of the thruster were built at the University of Arkansas in July 2015 and tested at NASA’s Marshall Space Flight Center in May 2018. Testing validated the viability of the LTCC thruster and provided valuable information on how to improve the thruster’s design.
Conducted Emi Mitigation In Power Converters Using Active Emi Filters, Balaji Narayanasamy
Conducted Emi Mitigation In Power Converters Using Active Emi Filters, Balaji Narayanasamy
Graduate Theses and Dissertations
Wide bandgap devices enable high power density power converters. Despite the advantages of increased switching frequency, the passive components are still a major bottleneck towards enabling high power density. Among the passive components in the converter, the passive EMI filters are unavoidable to ensure compliance with conducted EMI standards. Active EMI filters help reduce the volume of the passive components and have been around for three decades now. Firstly, this work presents a summary of all the different active EMI filters based on the type of noise-sensing, noise-processing, the type of active circuits used and the type of control methods. …
Multimode-Interference Based Optical Fiber Sensor For Civil Structures Monitoring, Sue Ping Chew
Multimode-Interference Based Optical Fiber Sensor For Civil Structures Monitoring, Sue Ping Chew
Student Works (2020-2029)
The thesis describes the experimental investigations on the multimode interferencebased fiber sensors using single mode multimode single mode (SMS) and multimode single mode multimode (MSM) structures as a sensing device for structural health monitoring (SHM) applications. Both sensor structures were fabricated, characterized and tested for detecting strain and vibration in civil infrastructures. The proposed SMS structure comprises of a short segment of multimode fiber (MMF), which were fusionspliced by two single mode fibers (SMFs) at both terminals. On the other hand, MSM was fabricated by splicing SMF with MMF at both ends. A new packaging technique for the SMS structure …
Rugged Linear Array For Iot Applications, Lidong Chi, Zi Bin Weng, Shu Meng, Yihong Qi, Jun Fan, Weihua Zhuang, James L. Drewniak
Rugged Linear Array For Iot Applications, Lidong Chi, Zi Bin Weng, Shu Meng, Yihong Qi, Jun Fan, Weihua Zhuang, James L. Drewniak
Electrical and Computer Engineering Faculty Research & Creative Works
In this article, a rugged linear array is proposed for covering both the LTE and 5G bands with an intermediate gain. The antenna is composed of a driven element, a set of directors, and a set of reflectors, where the excited element is a wideband high-efficiency electromagnetic structure (WHEMS) and the parasitic elements consist of metal rods. To achieve a rugged design, similar to the classic Yagi antenna, all of the elements should be conductively connected, so that it can be welded. The weldable mechanism is started on the driven radiating element. In addition, a balun is introduced in the …
Neutrino Detection Antenna, Samuel D. Keechler
Neutrino Detection Antenna, Samuel D. Keechler
Electrical Engineering
Neutrinos carry valuable information about deep space events that researchers can utilize to study the early universe. Since the first neutrino was detected in 1956, it is a relatively new physics research topic. A new state-of-the-art research facility, the Radio Neutrino Observatory in Greenland (RNO-G), was developed to detect Ultra-High Energy (UHE) neutrinos, ones with energy greater than 100 PeV (1015 electronvolts). For reference, this amount of energy lifts an apple 5 cm, or drives a neutrino, a particle 1034 times smaller by mass, near the speed of light [1]. UHE neutrino events typically occur less than five times a …
High Efficiency Rf Amplifier Design, Evan W. Johnson
High Efficiency Rf Amplifier Design, Evan W. Johnson
Electrical Engineering
High efficiency RF power amplifiers are key to the operation of modern wireless systems. From reducing power consumption at base stations to increasing battery life in handsets, high efficiency amplifiers help system designers to meet key performance criteria for their customers. The advent of the Internet of Things and 5G will lead to mass proliferation of battery operated wireless devices, increasing demand for high efficiency systems. In this project, a high efficiency 4W narrowband PA operating at 1GHz is designed, built and tested for the IMS2020 high efficiency power amplifier (HEPA) design competition. Emphasis is placed on achieving maximum power-added …
Short-Baseline High-Precision Dgps For Smart Snow Blower, Yunlong Luo, Zi Bin Weng, Yihong Qi, Lei Deng, Wei Yu, Fuhai Li, James L. Drewniak, Weihua Zhuang, Miao Miao, Jing Huang
Short-Baseline High-Precision Dgps For Smart Snow Blower, Yunlong Luo, Zi Bin Weng, Yihong Qi, Lei Deng, Wei Yu, Fuhai Li, James L. Drewniak, Weihua Zhuang, Miao Miao, Jing Huang
Electrical and Computer Engineering Faculty Research & Creative Works
High-precision positioning is critical for many Internet-of-Things (IoT) applications; however, most existing approaches are too expensive to be used in commercial products. A highly accurate differential global positioning system (DGPS) has not been widely used because of the difficulty in solving integer ambiguities in the single-frequency carrier phase. Multipath interference and receiver noise are the main reasons for limiting the DGPS accuracy and efficiency in solving integer ambiguities. In this article, we propose a combination of anti-multipath antennas and high-performance GPS receivers to effectively mitigate impairments due to multipath propagation and receiver noise. Furthermore, by exploiting more data available from …
Performance Analysis For Single-Stage And Multi-Stage Coreless Axial Flux Permanent Magnet Generator With Different Rotor Structures, Habib Asiful
Student Works (2020-2029)
Axial flux permanent magnet (AFPM) generator is a good candidate for both low and high-speed applications. Compared to radial flux machines, AFPM generators can be easily cascaded for enhanced power/torque while maintaining a fixed machine diameter. To improve power density and reduce cogging torque, some researchers have proposed the removal of iron core in the stator of AFPM machine, giving rise to the concept of coreless AFPM machine. Nevertheless, most of these coreless machines still require back iron on the rotor and/stator to reduce leakage flux. In this project, different rotor structures for single-stage coreless AFPM generators were considered, using …
The Characterization Of Effective Electromagnetic Fields On The Safety And Quality Of Low-Moisture Foods (Effs) - Prototype Device Development, Joe G. Sandoval
The Characterization Of Effective Electromagnetic Fields On The Safety And Quality Of Low-Moisture Foods (Effs) - Prototype Device Development, Joe G. Sandoval
Electrical Engineering
Contamination of low-moisture foods including flour, wheat grain, baby formula, and more, have increasingly become a concern due to sanitizing challenges. While industrial food processors have long used RF heating to sanitize mass quantities, an equivalent consumer device is absent from the market today. The Characterization of Effective Electromagnetic Fields on the Safety and Quality of Low-Moisture Foods (EEFS) project is an interdisciplinary effort to develop an RF heating consumer device to sanitize low-moisture foods.
A prototype device was designed to sanitize low-moisture food items using RF heating acceptable for commercial or consumer applications.
Nondestructive Electromagnetic Characterization Of Uniaxial Sheet Media Using A Two-Flanged Rectangular Waveguide Probe, Neil G. Rogers, Michael J. Havrilla, Milo W. Hyde Iv, Alexander G. Knisely
Nondestructive Electromagnetic Characterization Of Uniaxial Sheet Media Using A Two-Flanged Rectangular Waveguide Probe, Neil G. Rogers, Michael J. Havrilla, Milo W. Hyde Iv, Alexander G. Knisely
Faculty Publications
Excerpt: Recent advancements in fabrication capabilities have renewed interest in the electromagnetic characterization of complex media, as many metamaterials are anisotropic and/or inhomogeneous. Additionally, for composite materials, anisotropy can be introduced by load, strain, misalignment, or damage through the manufacturing process [1], [2]. Methods for obtaining the constitutive parameters for isotropic materials are well understood and widely employed [3]–[8]. Therefore, it is crucial to develop a practical method for the electromagnetic characterization of anisotropic materials.