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Full-Text Articles in Engineering

Performance Analysis Of Vlc-Based Infrastructure-To-Vehicle Communication, Noura Elshabasy, Samy S. Soliman, Mohammad Abdellatif Aug 2023

Performance Analysis Of Vlc-Based Infrastructure-To-Vehicle Communication, Noura Elshabasy, Samy S. Soliman, Mohammad Abdellatif

Electrical Engineering

Infrastructure such as traffic signals are expected to communicate various safety messages as a part of the evolution of smart transportation networks. It is anticipated that hybrid Vehicle to Vehicle (V2V) and Infrastructure to Vehicle (I2V) communication links would be taken into account to further enhance the system performance and expand the reach and capacity of the network. This paper proposes a visible light communication (VLC) link by installing multiple Photo-Detectors (PDs) in I2V links in order to improve the Bit Error Rate (BER) performance of the system. The paper investigates the effect of the distances and received powers on …


Origin Of Capacitance In Perovskite Solar Cells: Insight Vision On The Energy Band Diagram, Ziad Khalifa, Sameh Abdellatif, Monica Roman Aug 2023

Origin Of Capacitance In Perovskite Solar Cells: Insight Vision On The Energy Band Diagram, Ziad Khalifa, Sameh Abdellatif, Monica Roman

Chemical Engineering

In recent years, perovskite solar cells (PSCs) have made significant progress, with fast improvements in energy conversion. Although they have become incredibly efficient in a short amount of time, they still face several obstacles before becoming a viable commercial technology. Researchers spent time looking for an equivalent circuit that could describe the J-V curves of PSCs and demonstrate the physical processes of optical absorption and carrier transit. In this paper, we proposed a model of perovskite solar cells (PSCs) using SCAPS software to determine the parasitic elements and show the solar cell's behavior. A previous model of a perovskite solar …


Optimized Beam-Forming For Massive Mimo- Ofdm System, Nelly M. Shafik, Hazem H. El-Banna Aug 2023

Optimized Beam-Forming For Massive Mimo- Ofdm System, Nelly M. Shafik, Hazem H. El-Banna

Mansoura Engineering Journal

Massive Multiple-Input Multiple-Output (MIMO) wireless communication systems, achieved by large number of antennas, is the main secrete of Fifth Generation (5G) wireless communication networks powerful. In this paper, novel active antennas selection algorithm is proposed with resulted in efficient system performance with only half number of antenna elements. In order to gain optimum performance of massive MIMO wireless communication systems, it is vital to well analyze channel models which is glory indication for massive MIMO system characteristics. In this paper, MIMO system is simulated in bad frequency selective fading channel which is considered the most matching channel in case of …


Comparing Current Consistency And Electrical Resistance Of Wearable Photovoltaic Cells Pre- And Post-Laundering And Pre- And Post-Corrosion Resistance Testing Conditions., Amit Talukder Aug 2023

Comparing Current Consistency And Electrical Resistance Of Wearable Photovoltaic Cells Pre- And Post-Laundering And Pre- And Post-Corrosion Resistance Testing Conditions., Amit Talukder

Theses and Dissertations

Photovoltaic(PV) technology is promising due to its natural availability among energy harvesting technologies. There is a growing need for sustainable power sources that can function without being connected to a power source or needing regular battery replacements. Wearable PV cells are gaining popularity in different applications. However, most companies produce wearable PVs for terrestrial applications. Research on wearable PV applications for the marine environment remains limited because these cells suffer from several issues. This research compares commercially sourced wearable PV cells' maximum current consistency and electrical resistance for two testing conditions. The researcher followed standardized methods for these two laundering …


Physical Layer Security With Unmanned Aerial Vehicles For Advanced Wireless Networks, Aly Sabri Abdalla Aug 2023

Physical Layer Security With Unmanned Aerial Vehicles For Advanced Wireless Networks, Aly Sabri Abdalla

Theses and Dissertations

Unmanned aerial vehicles (UAVs) are emerging as enablers for supporting many applications and services, such as precision agriculture, search and rescue, temporary network deployment, coverage extension, and security. UAVs are being considered for integration into emerging wireless networks as aerial users, aerial relays (ARs), or aerial base stations (ABSs). This dissertation proposes employing UAVs to contribute to physical layer techniques that enhance the security performance of advanced wireless networks and services in terms of availability, resilience, and confidentiality. The focus is on securing terrestrial cellular communications against eavesdropping with a cellular-connected UAV that is dispatched as an AR or ABS. …


Resource Optimization Of Edge Servers Dealing With Priority-Based Workloads By Utilizing Service Level Objective-Aware Virtual Rebalancing, Amna Shahid Aug 2023

Resource Optimization Of Edge Servers Dealing With Priority-Based Workloads By Utilizing Service Level Objective-Aware Virtual Rebalancing, Amna Shahid

Theses and Dissertations

IoT enables profitable communication between sensor/actuator devices and the cloud. Slow network causing Edge data to lack Cloud analytics hinders real-time analytics adoption. VRebalance solves priority-based workload performance for stream processing at the Edge. BO is used in VRebalance to prioritize workloads and find optimal resource configurations for efficient resource management. Apache Storm platform was used with RIoTBench IoT benchmark tool for real-time stream processing. Tools were used to evaluate VRebalance. Study shows VRebalance is more effective than traditional methods, meeting SLO targets despite system changes. VRebalance decreased SLO violation rates by almost 30% for static priority-based workloads and 52.2% …


Exploring Bistatic Scattering Modeling For Land Surface Applications Using Radio Spectrum Recycling In The Signal Of Opportunity Coherent Bistatic Simulator, Dylan R. Boyd Aug 2023

Exploring Bistatic Scattering Modeling For Land Surface Applications Using Radio Spectrum Recycling In The Signal Of Opportunity Coherent Bistatic Simulator, Dylan R. Boyd

Theses and Dissertations

The potential for high spatio-temporal resolution microwave measurements has urged the adoption of the signals of opportunity (SoOp) passive radar technique for use in remote sensing. Recent trends in particular target highly complex remote sensing problems such as root-zone soil moisture and snow water equivalent. This dissertation explores the continued open-sourcing of the SoOp coherent bistatic scattering model (SCoBi) and its use in soil moisture sensing applications. Starting from ground-based applications, the feasibility of root-zone soil moisture remote sensing is assessed using available SoOp resources below L-band. A modularized, spaceborne model is then developed to simulate land-surface scattering and delay-Doppler …


Determining Student Attentiveness By Use Of Heart Rate Measurement Using A Wearable Device, Erik Rhodes Brown Aug 2023

Determining Student Attentiveness By Use Of Heart Rate Measurement Using A Wearable Device, Erik Rhodes Brown

Theses and Dissertations

Distraction from personal technology is a widely recognized problem in the modern classroom. Further, instructors have limited abilities to determine when students are waxing or waning in attentiveness. This evaluative experiment leverages the Apple Watch’s heart rate sensors to capture signs of attentiveness in participants simulating remote university lectures of differing interest levels as determined by YouTube commenters. Once captured, the heart rate data separated and analyzed to determine the effect of the lecture treatment on the participants’ heart rates. Twenty-seven students from Mississippi State University’s Electrical and Computer Engineering and Computer Science and Engineering departments elected to participate in …


Vertical Federated Learning Using Autoencoders With Applications In Electrocardiograms, Wesley William Chorney Aug 2023

Vertical Federated Learning Using Autoencoders With Applications In Electrocardiograms, Wesley William Chorney

Theses and Dissertations

Federated learning is a framework in machine learning that allows for training a model while maintaining data privacy. Moreover, it allows clients with their own data to collaborate in order to build a stronger, shared model. Federated learning is of particular interest to healthcare data, since it is of the utmost importance to respect patient privacy while still building useful diagnostic tools. However, healthcare data can be complicated — data format might differ across providers, leading to unexpected inputs and incompatibility between different providers. For example, electrocardiograms might differ in sampling rate or number of leads used, meaning that a …


Non-Destructive Evaluation Of White Striping And Microbial Spoilage Of Broiler Breast Meat Using Structured-Illumination Reflectance Imaging, Ebenezer O. Olaniyi Aug 2023

Non-Destructive Evaluation Of White Striping And Microbial Spoilage Of Broiler Breast Meat Using Structured-Illumination Reflectance Imaging, Ebenezer O. Olaniyi

Theses and Dissertations

Manual inspection is a prevailing practice for quality assessment of poultry meat, but it is labor-intensive, tedious, and subjective. This thesis aims to assess the efficacy of an emerging structured illumination reflectance imaging (SIRI) technique with machine learning approaches for assessing WS and microbial spoilage in broiler breast meat. Broiler breast meat samples were imaged by an in house-assembled SIRI platform under sinusoidal illumination. In first experiment, handcrafted texture features were extracted from direct component (DC, corresponding to conventional uniform illumination) and amplitude component (AC, unique to the use of sinusoidal illumination) images retrieved from raw SIRI pattern images build …


Modeling Of Signals And Spectra: 5g And Beyond, Xianzhen Yang Aug 2023

Modeling Of Signals And Spectra: 5g And Beyond, Xianzhen Yang

Dissertations and Theses

The collection of papers addresses various aspects of spectra and signals in RF wireless systems for 5G and beyond. The first paper focuses on the nonlinear effects of amplified dual-band OFDM signals, providing a spectrum model for intermodulation and cross-modulation. The second paper extends this analysis beyond bandwidth restrictions, enabling accurate prediction of amplified dual-band spectrum. The third paper emphasizes the significance of out-of-band intermodulation products and derives an analytical expression using third-order intercept points. The fourth paper presents a unified spectrum expression for OFDM, FBMC, and F-OFDM, facilitating comparative insights into these signals. The fifth paper explores second-order intermodulation …


Potential Of Mirnas In Plasma Extracellular Vesicle For The Stratification Of Prostate Cancer In A South African Population, Dada Oluwaseyi Temilola, Martha Wium, Juliano Paccez, Azola Samkele Salukazana, Hasan H. Otu, Giuseppina M. Carbone, Lisa Kaestner, Stefano Cacciatore, Luiz Fernando Zerbini Aug 2023

Potential Of Mirnas In Plasma Extracellular Vesicle For The Stratification Of Prostate Cancer In A South African Population, Dada Oluwaseyi Temilola, Martha Wium, Juliano Paccez, Azola Samkele Salukazana, Hasan H. Otu, Giuseppina M. Carbone, Lisa Kaestner, Stefano Cacciatore, Luiz Fernando Zerbini

Department of Electrical and Computer Engineering: Faculty Publications

Prostate cancer (PCa) is the most common cause of cancer death among African men. The analysis of microRNAs (miRNAs) in plasma extracellular vesicles (EVs) can be utilized as a non-invasive tool for the diagnosis of PCa. In this study, we used small RNA sequencing to profile miRNAs cargo in plasma EVs from South African PCa patients. We evaluated the differential expression of miRNAs between low and high Gleason scores in the plasma EVs of South African patients and in the prostatic tissue from data available in the Cancer Genome Atlas (TCGA) Data Portal. We identified 7 miRNAs differently expressed in …


A Method For Economic Expansion Planning Of Transmission Networks Using Heuristic Rules And Non-Linear Optimization Model, Maged Gamal Lotfy, Mahmoud Ali Farrag, Mohamed Shibl Albags, Ahmed Hamdy Khalil Aug 2023

A Method For Economic Expansion Planning Of Transmission Networks Using Heuristic Rules And Non-Linear Optimization Model, Maged Gamal Lotfy, Mahmoud Ali Farrag, Mohamed Shibl Albags, Ahmed Hamdy Khalil

Mansoura Engineering Journal

This paper presents a method for economic planning of transmission networks in an iterative manner. The method is capable of solving large scale networks where the most "worst" new lines are deleted iteratively using heuristic rules. In each iteration, a relatively small size non-linear mathematical Programming model is built to enhance the deletion process. The non-linear model is based on full AC load flow where only the reactive power injected from different available reactive power sources are controlled plus the reference bus voltage magnitude. The deletion process is stopped when the deleting of any line from the rest set of …


Efficient Scopeformer: Toward Scalable And Rich Feature Extraction For Intracranial Hemorrhage Detection, Yassine Barhoumi, Nidhal Carla Bouaynaya, Ghulam Rasool Aug 2023

Efficient Scopeformer: Toward Scalable And Rich Feature Extraction For Intracranial Hemorrhage Detection, Yassine Barhoumi, Nidhal Carla Bouaynaya, Ghulam Rasool

Henry M. Rowan College of Engineering Departmental Research

The quality and richness of feature maps extracted by convolution neural networks (CNNs) and vision Transformers (ViTs) directly relate to the robust model performance. In medical computer vision, these information-rich features are crucial for detecting rare cases within large datasets. This work presents the “Scopeformer,” a novel multi-CNN-ViT model for intracranial hemorrhage classification in computed tomography (CT) images. The Scopeformer architecture is scalable and modular, which allows utilizing various CNN architectures as the backbone with diversified output features and pre-training strategies. We propose effective feature projection methods to reduce redundancies among CNN-generated features and to control the input size of …


Integration Of Meta-Multi-Omics Data Using Probabilistic Graphs And External Knowledge, Handan Can, Sree K. Chanumolu, Barbara D. D., Sophie Alvarez, Michael J. Naldrett, Gülhan Ünlü, Hasan H. Otu Aug 2023

Integration Of Meta-Multi-Omics Data Using Probabilistic Graphs And External Knowledge, Handan Can, Sree K. Chanumolu, Barbara D. D., Sophie Alvarez, Michael J. Naldrett, Gülhan Ünlü, Hasan H. Otu

Department of Electrical and Computer Engineering: Faculty Publications

Multi-omics has the promise to provide a detailed molecular picture of biological systems. Although obtaining multi-omics data is relatively easy, methods that analyze such data have been lagging. In this paper, we present an algorithm that uses probabilistic graph representations and external knowledge to perform optimal structure learning and deduce a multifarious interaction network for multi-omics data from a bacterial community. Kefir grain, a microbial community that ferments milk and creates kefir, represents a self-renewing, stable, natural microbial community. Kefir has been shown to have a wide range of health benefits. We obtained a controlled bacterial community using the two …


Sel4 On Risc-V - Developing High Assurance Platforms With Modular Open-Source Architectures, Michael A. Doran Jr Aug 2023

Sel4 On Risc-V - Developing High Assurance Platforms With Modular Open-Source Architectures, Michael A. Doran Jr

Masters Theses

Virtualization is now becoming an industry standard for modern embedded systems. Modern embedded systems can now support multiple applications on a single hardware platform while meeting power and cost requirements. Virtualization on an embedded system is achieved through the design of the hardware-software interface. Instruction set architecture, ISA, defines the hardware-software interface for an embedded system. At the hardware level the ISA, provides extensions to support virtualization.

In addition to an ISA that supports hypervisor extensions it is equally important to provide a hypervisor completely capable of exploiting the benefits of virtualization for securing modern embedded systems. Currently there does …


Consensus-Based Active And Reactive Power Control And Management Of Microgrids, Shruti Singh Aug 2023

Consensus-Based Active And Reactive Power Control And Management Of Microgrids, Shruti Singh

Electronic Theses and Dissertations

Microgrids incorporating distributed generation and renewable energy sources offer potential solutions to the energy crisis while modernizing traditional grids. Despite cost-effectiveness in some technologies, financial support remains crucial for expensive ones like PV, fuel cells, and storage technologies. Microgrids bring economic benefits, efficiency, reduced emissions, and improved power quality. Their success hinges on cost reductions in renewables, storage, reliability, and energy management systems, enabling operation both with and without the utility grid.

Economic Dispatch optimizes system costs, considering all constraints. Various methods tackle this problem, including quadratic convex functions, Lagrangian relaxation, and quadratic programming. For microgrids with distributed generators, seamless …


Optimal Sizing And Safe Management Of Lithium-Ion Batteries In High Voltage Power Systems, Hayden Lee Atchison Aug 2023

Optimal Sizing And Safe Management Of Lithium-Ion Batteries In High Voltage Power Systems, Hayden Lee Atchison

Electrical Engineering Dissertations - Archive

Lithium-ion batteries have gained widespread use in various applications, but safety challenges persist due to errors in assembly and faulty electronics management. Ensuring safety and reliable operation in large batteries containing numerous series/parallel cells demand innovative monitoring technologies. Elevated temperatures resulting from normal or abnormal operation are a major cause of battery failure, necessitating effective temperature monitoring techniques. Similarly, abnormal stress/strain signatures offer valuable diagnostic information. In the study discussed here, the application of a Optical Distributed Sensor Interrogator (ODiSI) employing high-definition fiber optic sensors (HD-FOS) for measuring surface temperature and case deformation of 18650 cells under normal and abnormal …


Hardware In The Loop Test Stand For Battery Management System Validation In Shipboard Controls, Cole Dawson Tschritter Aug 2023

Hardware In The Loop Test Stand For Battery Management System Validation In Shipboard Controls, Cole Dawson Tschritter

Electrical Engineering Dissertations - Archive

ABSTRACT: Traditionally, large-scale power systems have relied on power generation always exceeding the total load demand. Though this is most often the case, there are rare occurrences where failures in the generation, distribution, or even planning, that have led to situations where load demand quickly surpasses the generation capacity. In such cases, uncontrolled shedding of loads occurs, leading to brownouts or blackouts that can have catastrophic impact to both people and property. Advanced architectures, such as microgrids, offer a variety of improvements that are aimed at mitigating or even preventing these failures. Improvements include distributed power generation, active source and …


Assessment Of Land And Renewable Energy Resource Potential For Regional Power System Integration With Ml Spatio-Temporal Clustering, Rosemary E. Alden, Claire Halloran, Donovin D. Lewis, Dan M. Ionel Aug 2023

Assessment Of Land And Renewable Energy Resource Potential For Regional Power System Integration With Ml Spatio-Temporal Clustering, Rosemary E. Alden, Claire Halloran, Donovin D. Lewis, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Toward the planning and development of future electric power systems with extremely large penetration of renewable resources (DERs), detailed assessment of power and energy potential is needed considering both spatial and temporal data per region. Within this paper, a methodology for spatio-temporal DER capacity potential considering land cover types and weather variation are presented using spatio-temporal data. Additionally, an application of empirical orthogonal functions (EOFs) and max-p unsupervised learning techniques is proposed for DER generation to identify zones of similar output power in space and time. A detailed case study for the example region of Kentucky, USA is completed with …


Tunable Linewidth Chip-Level Lasers Using Hybrid Integration Methods, Charles Porter Aug 2023

Tunable Linewidth Chip-Level Lasers Using Hybrid Integration Methods, Charles Porter

All Theses

Photonic integrated circuits (PICs) have significant value in today’s world of research. They enable devices to experience large reductions in size, weight, operation power, and cost (SWAPc), making photonic technology more accessible than ever. The functionality of PICs is greatly enhanced due to the realization of both active and passive devices within a single device structure. This is made possible through hybrid integration, which utilizes various coupling methods to transfer light from an active chip to a passive chip. Hybrid integration technology tremendously expands the capabilities of PICs, leading to a plethora of applications. One significant application is that of …


Wirelessly Powering A Sea Of Sensors For Perimeter Security Applications, Ian River Chavez Aug 2023

Wirelessly Powering A Sea Of Sensors For Perimeter Security Applications, Ian River Chavez

Electrical and Computer Engineering ETDs

his thesis presents an innovative application of Inductive Power Transfer (IPT) technology for perimeter security systems. The approach leverages the physical properties of IPT to detect intrusions by monitoring voltage changes in wirelessly powered sensor nodes, which can double as components of an intrusion detection system. Disturbances in node orientation, indicative of potential intrusions, alter the sensor node’s resonant frequency and create measurable voltage shifts. This study explores the concept in-depth, from the analysis of resonant inductive coupling in various resonant inductive modes, to the design of transmit loops, sensor nodes, and the techniques required to ensure optimum power transfer. …


Noise-Resilient And Adaptive Distributed Control Techniques For Microgrids, Seyed Iman Habibi Aug 2023

Noise-Resilient And Adaptive Distributed Control Techniques For Microgrids, Seyed Iman Habibi

Electrical and Computer Engineering ETDs

This dissertation focuses on addressing the critical tasks of secondary control in microgrids, particularly in the islanding operating mode. The presence of noise in sensors and communication links necessitates the design of a noise-resilient secondary control approach. In response, this dissertation introduces the Nonlinear Generalized Minimum Variance (NGMV) control approach into the islanded AC and DC microgrid's secondary control system. The effectiveness of the proposed approach is demonstrated through MATLAB simulations. Additionally, the dissertation presents an adaptive, model-free, and data-driven control approach for secondary voltage control in AC microgrids, addressing uncertainties. By employing Unfalsified Adaptive Control (UAC), the approach selects …


A Study Of 5g Cellular Connectivity To Unmanned Aerial Vehicles, Jackson Murrin Aug 2023

A Study Of 5g Cellular Connectivity To Unmanned Aerial Vehicles, Jackson Murrin

All Theses

The market of unmanned aerial vehicles (UAVs) has seen significant growth in the past ten years on both the commercial and military sides. The applications for UAVs are endless and options by manufacturers allow users to modify their drones for their specific goals. This industry has opened up the excitement of piloting vehicles in the air, photography, videography, exploration of nature from a different point of view and many other hobbies assisted by the emergence of UAVs. The growth of this industry coincides with the roll out of new 5G cellular network technology. This upgrade in cellular network infrastructure allows …


Generalizable Deep-Learning-Based Wireless Indoor Localization, Ali Owfi Aug 2023

Generalizable Deep-Learning-Based Wireless Indoor Localization, Ali Owfi

All Theses

The growing interest in indoor localization has been driven by its wide range of applications in areas such as smart homes, industrial automation, and healthcare. With the increasing reliance on wireless devices for location-based services, accurate estimation of device positions within indoor environments has become crucial. Deep learning approaches have shown promise in leveraging wireless parameters like Channel State Information (CSI) and Received Signal Strength Indicator (RSSI) to achieve precise localization. However, despite their success in achieving high accuracy, these deep learning models suffer from limited generalizability, making them unsuitable for deployment in new or dynamic environments without retraining. To …


A Portable, Low Power Radiation Detection And Identification System For High Count Rate, Long Term Monitoring, Samuel J. Murray Aug 2023

A Portable, Low Power Radiation Detection And Identification System For High Count Rate, Long Term Monitoring, Samuel J. Murray

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

This dissertation presents the design of a novel radiation detection and identification system that can operate continuously over a period of 8 days while detecting at 30,000 counts per second, consuming a total of 11 mW. The entire system is highly integrated, containing a gamma ray detector, a high voltage detector power supply, and a multichannel analyzer (MCA) system-on-a-chip (SoC), which are all combined into a compact form using a multi-level, configurable printed circuit board design. The MCA SoC, fabricated using a 65 nm CMOS technology, features two enabling resources to allow low power detections at high count rates for …


Cross-Layer Cryptography For Wireless Communication, Hesham Mohammed Aug 2023

Cross-Layer Cryptography For Wireless Communication, Hesham Mohammed

Legacy Theses & Dissertations (2009 - 2024)

Spectrum access in the next-generation wireless networks will be congested, competitive, and vulnerable to malicious intents of strong adversaries. This motivates us to rethink secure wireless communication in a zero-trust electromagnetic environment. Classical cryptography is an add-on feature that provides semantic security between trusted partners at higherlayers. However, cryptography ignores cross-layer interaction with physical layer which is required to enhance the secrecy level of the transmitted waveform. Moreover, cryptographic schemes might no longer be secure in the quantum era. Physical layer security (PLS) is introduced as a complement to cryptography, where security is provided in the physical layer using the …


A Direct Data Approach To Joint 2-D Doa And Frequency Estimation With L-Shaped Array, Yanming Zhang, Lijun Jiang Aug 2023

A Direct Data Approach To Joint 2-D Doa And Frequency Estimation With L-Shaped Array, Yanming Zhang, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

This article presents a joint two-dimensional dynamic mode decomposition (JTDDMD) approach to estimate the azimuth angle, elevation angle, and frequency for multiple narrowband sources using the L-shaped array. According to the placement position of different coordinate axes of the receiving antenna in the array, i.e., x- or z-axis, the received signal is divided into two datasets. Two-dimensional dynamic mode decomposition (TDDMD), the sub algorithm of JTDDMD, is used twice to deal with these two datasets separately. Through the analysis of the x-axis subarray received signal using TDDMD, the electrical angle in the x-direction and frequency are obtained with automatic pairing. …


Spectral Broadening Effects On Pulsed-Source Digital Holography, Steven A. Owens, Mark F. Spencer, Glen P. Perram Aug 2023

Spectral Broadening Effects On Pulsed-Source Digital Holography, Steven A. Owens, Mark F. Spencer, Glen P. Perram

Faculty Publications

Using a pulsed configuration, a digital-holographic system is setup in the off-axis image plane recording geometry, and spectral broadening via pseudo-random bit sequence is used to degrade the temporal coherence of the master-oscillator laser. The associated effects on the signal-to-noise ratio are then measured in terms of the ambiguity and coherence efficiencies. It is found that the ambiguity efficiency, which is a function of signal-reference pulse overlap, is not affected by the effects of spectral broadening. The coherence efficiency, on the other hand, is affected. As a result, the coherence efficiency, which is a function of effective fringe visibility, is …


Localization And Identification Of Emi Sources In Shielding Enclosures Based On A Two-Step Source Reconstruction Method, Zi An Wang, Jun Fa Mao, Li (Lijun) Jun Jiang, Ping Li Aug 2023

Localization And Identification Of Emi Sources In Shielding Enclosures Based On A Two-Step Source Reconstruction Method, Zi An Wang, Jun Fa Mao, Li (Lijun) Jun Jiang, Ping Li

Electrical and Computer Engineering Faculty Research & Creative Works

Localization and identification of unknown electromagnetic interference (EMI) sources in shielding enclosures is a great challenge due to the complex electromagnetic environment. In this work, a two-step source reconstruction method is proposed to address this issue. The actual EMI sources are initially modeled by equally distributed equivalent electric dipoles in the shielding enclosure. Effects of surrounding environments are rigorously incorporated using the numerical Green's function which bridges between the equivalent dipoles and planar scanned tangential magnetic near-field. Next, the initial equivalent sources are downsized via evaluating the contribution of each equivalent dipole. The parameters of remaining equivalent dipoles are updated …