Electrical and Computer Engineering Commons^™

Protecting Return Address Integrity For Risc-V Via Pointer Authentication, Yuhe Zhao

Masters Theses

Embedded systems based on lightweight microprocessors are becoming more prevalent in various applications. However, the security of them remains a significant challenge due to the limited resources and exposure to external threats. Especially, some of these devices store sensitive data and control critical devices, making them high-value targets for attackers. Software security is particularly important because attackers can easily access these devices on the internet and obtain control of them by injecting malware.

Return address (RA) hijacking is a common software attack technique used to compromise control flow integrity (CFI) by manipulating memory, such as return-to-libc attacks. Several methods have …

Blockchain Design For A Secure Pharmaceutical Supply Chain, Zhe Xu

Masters Theses

In the realm of pharmaceuticals, particularly during the challenging times of the COVID-19 pandemic, the supply chain for drugs has faced significant strains. The increased demand for vaccines and therapeutics has revealed critical weaknesses in the current drug supply chain management systems. If not addressed, these challenges could lead to severe societal impacts, including the rise of counterfeit medications and diminishing trust in government authorities.

The study identified that more than the current strategies, such as the Drug Supply Chain Security Act (DSCSA) in the U.S., which focuses on unique authentication and traceability codes for prescription drugs, is needed to …

Open-Ended Hollow Coaxial Cable Resonance Sensing Via Permittivity Fluctuations For Applications To Exhaled Breath Health Monitoring, Peter Henry Holtmann

Masters Theses

"We report a pre-diagnostics breath analyzer based on the open-ended hollow coaxial cable resonator (OE-HCCR) to achieve real-time differentiation of healthy and compromised lung function through electromagnetic analysis of exhaled breath matter. A two-phase amplification scheme of electromagnetic signatures metered via the S11 phase curve offers high sensitivity to permittivity fluctuations in exposed airflow. The mathematical model of the breath analyzer is explained, followed by experimental validation of numerical findings from previous work. The collection of breath transient signals is performed through monitoring the reflected power magnitude and phase of the scattering parameter (S11) at the resonance frequency. Material fluctuations …

A Case Study In Cmos Design Scaling For Analog Applications: The Ringamp Ldo, Steven Corum

Masters Theses

As CMOS process nodes scale to smaller feature sizes, process optimizations are made to achieve improvements in digital circuit performance, such as increasing speed and memory, while decreasing power consumption. Unfortunately for analog design, these optimizations usually come at the expense of poorer transistor performance, such as reduced small signal output resistance and increased channel length modulation. The ring amplifier has been proposed as a digital solution to the analog scaling problem, by configuring digital inverters to function as analog amplifiers through deadzone biasing. As digital inverters naturally scale, the ring amplifier is a promising area of exploration for analog …

Analog Cancellation Of A Known Remote Interference: Hardware Realization And Analysis, James M. Doty

Masters Theses

The onset of quantum computing threatens commonly used schemes for information secrecy across wireless communication channels, particularly key-based data-level encryption. This calls for secrecy schemes that can provide everlasting secrecy resistant to increased computational power of an adversary. One novel physical layer scheme proposes that an intended receiver capable of performing analog cancellation of a known key-based interference would hold a significant advantage in recovering small underlying messages versus an eavesdropper performing cancellation after analog-to-digital conversion. This advantage holds even in the event that an eavesdropper can recover and use the original key in their digital cancellation. Inspired by this …

A Feasibility Study Of A Wearable Health Monitoring Device Powered By Thermoelectric Generators, Sarah Schneider

Masters Theses

Implementation of thermoelectric generators (TEGs) as a power source for embedded systems has increased with the push toward alternative and renewable energy sources. Thermoelectric generators produce electrical energy from thermal energy through the Seebeck effect. The Seebeck effect is a phenomenon seen when a temperature difference at a joint of two different metals generates a DC current and electromotive force [1]. This has made TEGs desirable for embedded system applications because it would allow for extended wireless operation. TEGs are based on solid-state technology which means they do not consist of any moving parts which reduces wear and tear with …

Fingerprinting For Chiplet Architectures Using Power Distribution Network Transients, Matthew G. Burke

Masters Theses

Chiplets have become an increasingly popular technology for extending Moore's Law and improving the reliability of integrated circuits. They do this by placing several small, interacting chips on an interposer rather than the traditional, single chip used for a device. Like any other type of integrated circuit, chiplets are in need of a physical layer of security to defend against hardware Trojans, counterfeiting, probing, and other methods of tampering and physical attacks.

Power distribution networks are ubiquitous across chiplet and monolithic ICs, and are essential to the function of the device. Thus, we propose a method of fingerprinting transient signals …

Design And Fabrication Of A Trapped Ion Quantum Computing Testbed, Christopher A. Caron

Masters Theses

Here we present the design, assembly and successful ion trapping of a room-temperature ion trap system with a custom designed and fabricated surface electrode ion trap, which allows for rapid prototyping of novel trap designs such that new chips can be installed and reach UHV in under 2 days. The system has demonstrated success at trapping and maintaining both single ions and cold crystals of ions. We achieve this by fabricating our own custom surface Paul traps in the UMass Amherst cleanroom facilities, which are then argon ion milled, diced, mounted and wire bonded to an interposer which is placed …

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 …

Approximate And Sample Entropy Of Center Of Pressure In Unperturbed Tandem Standing: Contribution Of Embedding Dimension And Tolerance, Jayla Mashae Wesley

Masters Theses

Approximate entropy (ApEn) and sample entropy (SampEn) are statistical methods designed to quantify the regularity or predictability of a time series. Although ApEn has been a prominent choice for use, it is currently unclear as to which method and parameter selection combination is optimal for its application in biomechanics. The goal of this thesis was to examine the difference between ApEn and SampEn related to center of pressure (COP) data during standing balance tasks, while also refining tolerance r, to determine entropy optimization. Six participants completed five 30-second, feet together and tandem standing, trials under eyes-open and eyes-closed conditions. Ground …

An Isostable Coordinate Based Amelioration Strategy To Mitigate The Effects Of Jet Lag, Talha Ahmed

Masters Theses

Commercial air travel has become extremely commonplace in the last 20 to 30 years especially as the world has moved towards new heights of globalization. Though air travel has greatly reduced transit times allowing people to cover thousand of miles within hours, it comes with its fair share of issues. jet-lag can be regarded to be at the top of those list of problems; jet-lag typically results from rapid travel through multiple time zones which causes a significant misalignment between the person's internal circadian clock and the external time. A person's circadian clock is governed by a population of coupled …

A Low Power, Rad-Hard, Ecl Standard Cell Library, Zakaraya A. Hamdan

Masters Theses

Space exploration for life both inside and outside of our solar system demand the design and fabrication of robust, reliable electronics that can take measurements, process data, and sustain necessary operations. However, the presence of high radiation and the cold temperature of space poses a challenge to most designers. This thesis presents the design of a radiation-hardened, cold capable emitter coupled logic standard cell library with the intention of being used for space applications. The cells are designed and fabricated in a 90nm silicon germanium BiCMOS process. First, a review of emitter coupled logic is presented. Then, the design methodology …

Electrothermal Properties Of 2d Materials In Device Applications, Samantha L. Klein

Masters Theses

To keep downsizing transistors, new materials must be explored since traditional 3D materials begin to experience tunneling and other problematic physical phenomena at small sizes. 2D materials are appealing due to their thinness and bandgap. The relatively weak van der Waals forces between layers in 2D materials allow easy exfoliation and device fabrication but they also result in poor heat transfer to the substrate, which is the main path for heat removal. The impaired thermal coupling is exacerbated in few-layer devices where heat dissipated in the layers further from the substrate encounters additional interlayer thermal resistance before reaching the substrate, …

Heterogeneous Iot Network Architecture Design For Age Of Information Minimization, Xiaohao Xia

Masters Theses

Timely data collection and execution in heterogeneous Internet of Things (IoT) networks in which different protocols and spectrum bands coexist such as WiFi, RFID, Zigbee, and LoRa, requires further investigation. This thesis studies the problem of age-of-information minimization in heterogeneous IoT networks consisting of heterogeneous IoT devices, an intermediate layer of multi-protocol mobile gateways (M-MGs) that collects and relays data from IoT objects and performs computing tasks, and heterogeneous access points (APs). A federated matching framework is presented to model the collaboration between different service providers (SPs) to deploy and share M-MGs and minimize the average weighted sum of the …

Improved Decap Model And Placement Optimization Algorithm For Power Distribution Network Design, Jack Juang

Masters Theses

"Decoupling capacitors (decaps) are used in power distribution network (PDN) design to act as a low impedance return path for noise and act as a local source of charge when required by integrated circuits (IC). For placement of decaps, which can number even to the hundreds, many algorithms have been proposed including genetic algorithms (GA), iterative algorithm, and machine learning methods.

One limitation of iterative decap placement algorithms (adding one decap at a time) is how the construction of the algorithm affects the form of the final solution. For example, if the reward function (used in GA and machine learning …

Prediction And Root-Cause Analysis For Smart Speaker Intentional Electromagnetic Interference Attacks, Tanner Fokkens

Masters Theses

"Smart home and Internet of Things (IoT) devices have become ubiquitous in homes over the past decade. The smart speaker itself is often the device that interfaces all these devices together. Because of this, the smart speaker can become a point of attack for someone trying to exploit or hack into the smart home devices. In the past few years, it was discovered that smart speakers with microwave electromechanical system (MEMS) microphones are susceptible to intentional electromagnetic interference (I-EMI) attacks by modulating an audio command to a high-frequency carrier signal. This attack allows for command recognition for long-distances and smart …

Static I-V Curve And Aging Test For Pim Characterization In Metallic Contacts, Kalkidan Anjajo

Masters Theses

"Spring clips and fabric-over-foams (FOFs) are widely used in mobile devices for electrical connection purposes. However, the imperfect metallic connections tend to induce passive intermodulation (PIM), resulting in a receiver sensitivity degradation, known as RF desensitization. Due to the complexity of the PIM characterization, there is not yet a way to evaluate PIM performance using a simple setup for environments like factories. In this study, a current-voltage (I-V) behavior-based PIM evaluation method is proposed and validated with various metallic contacts and contact forces. The test results demonstrated the feasibility of the PIM performance evaluation based on the measured static I-V …

A Real-Time Microwave Camera Using Zero-Bias Diode Detector, Liang Liu

Masters Theses

"This thesis presents the design of a microwave camera that utilizes a two-dimensional array of elliptical slot antennas and diode detectors to quickly and accurately locate radiation sources. Unlike traditional scanning techniques like ESM and holography, which rely on mechanical scanning, require a long measurement time, and are prone to mechanical errors, the microwave camera operates quickly and efficiently by using electronic switching to access the output of each detector. This results in a more precise and efficient means of locating radiation sources'--Abstract, p. iii

Application Of Load Shifting For Commercial Hvac-R Systems Via Static And Dynamic Event Automated Demand Response, Justin Anthony Martinez

Masters Theses

Life in the modern era is inextricably tied to energy and the unending, ever-growing need for more. The technologies that drive society, in fields such as communication, infrastructure, and heavy industry, are dependent on that electrical energy being reliable and readily available. This places an extreme importance on the power generation sector as a function of meeting the demand required for stability. However, as seen with increased climate volatility due to misused or otherwise mismanaged resources in the heavy industry, and the uncertain and variable renewable energy generation; there must also be ecological as well as economic consideration when discussing …

Electric Vehicle Aggregation Considering Fast-Charging For Power System Applications, Trey I. Mingee

Masters Theses

The electric grid has become one of the most important pieces of technology for modern society, providing power to homes and businesses at all hours of the day. Future increases of worldwide electricity demand along with growing threats of contingency scenarios such as cyberattacks cause great concerns regarding the reliability of the grid. Further, the gradual shift from fossil fuels to renewable energy sources creates a significant need for grid support services to aid in its operation. Electric vehicles will become more prevalent in coming decades; these modules present unique loads to the system that are prime candidates for use …

Formally Verifiable Synthesis Flow In Fpgas, Anurag V. Muttur

Masters Theses

FPGAs are used in a wide variety of digital systems. Due to their ability to support parallelism and specialization, these devices are becoming more commonplace in fields such as machine learning. One of the biggest benefits of FPGAs, logic specialization, can lead to security risks. Prior research has shown that a large variety of malicious circuits can snoop on sensitive user data, induce circuit faults, or physically damage the FPGA. These Trojan circuits can easily be crafted and embedded in FPGA designs. Often, these Trojans are small, consume little power in comparison to the target circuit, and are hard to …

Integration Of Digital Signal Processing Block In Symbiflow Fpga Toolchain For Artix-7 Devices, Andrew T. Hartnett

Masters Theses

The open-source community is a valuable resource for many hobbyists and researchers interested in collaborating and contributing towards publicly available tools. In the area of field programmable gate arrays (FPGAs) this is no exception. Contributors seek to reverse-engineer the functions of large proprietary FPGA devices. An interesting challenge for open-source FPGA engineers has been reverse-engineering the operation and bitstreams of digital signal processing (DSP) blocks located in FPGAs. SymbiFlow is an open-source FPGA toolchain designed as a free alternative to proprietary computer-aided design tools like Xilinx’s Vivado. For SymbiFlow, mapping logical multipliers to DSP blocks and generating DSP block bitstreams …

Load Modeling And Evaluation Of Leds For Hardware Test Bed Application, Jillian M. Ruff

Masters Theses

The lighting industry was revolutionized with the emergence of LED lighting. Over the last 15 years, LED lighting device sales and utilization have grown immensely. The growth and popularity of LEDs is due to improved operation of the device when compared to previous lighting technologies. Efficient performance of the device is critical due to the growth of global energy consumption.

As nonrenewable generation fuel is finite, utilities have begun the transition to renewable energy generation. Generation and distribution systems become inherently complex to comprehend and maintain with incorporation of emerging supply and load technologies. With the unprecedented growth of LED …

A Bulk Driven Transimpedance Cmos Amplifier For Sipm Based Detection, Shahram Hatefi Hesari

Masters Theses

The contribution of this work lies in the development of a bulk driven operational
transconducctance amplifier which can be integrated with other analog circuits and
photodetectors in the same chip for compactness, miniaturization and reducing the
power. Silicon photomultipliers, also known as SiPMs, when coupled with scintillator materials are used in many imaging applications including nuclear detection. This thesis discuss the design of a bulk-driven transimpedance amplifier suitable for detectors where the front end is a SiPM. The amplifier was design and fabricated in a standard standard CMOS process and is suitable for integration with CMOS based SiPMs and commercially …

Impacts Of Summer Drought And Climate Change Conditions On Hydropower Resources And Power System Reliability In The Pjm Region, William J. Tingen Ii

Masters Theses

The United States power grid is a large, complex, and interconnected system that involves the coordination of numerous entities (e.g., power plant owners/operators, regulators, stakeholders, etc.). As such, any type of extreme event can potentially threaten the economic, safe, and reliable operation of the grid. One such example is summer drought (i.e., events predominantly characterized by elevated temperatures and reduced precipitation), which have impacts spanning all aspects of the power system, especially generation resources through changes in water availability and temperature. Additionally, although heavily dependent on region, climate change can potentially increase the likelihood and severity of drought conditions, illustrating …

Theory And Analysis Of Backprojection Processing For Interferometric Sar, Marc Closa Tarres

Masters Theses

Synthetic Aperture Radar (SAR) is a well-known radar technique widely used for 2D and 3D imaging since the 1960s. SAR systems offer all-weather, day and night, high-resolution imaging by using the motion of the antenna over the target of interest. By later use of signal processing techniques, the received echoes can be put back together using precise knowledge of the system location and geometry to obtain the distinct high-resolution SAR imagery.

Moreover, when the system is equipped with multiple antennas, topography and topographic changes in the region of interest can be inferred using interferometric techniques.

The Microwave Remote Sensing Laboratory …

Design And Evaluation Of A Unique Weighted-Sum-Based Anger Camera, Matthew W. Seals

Masters Theses

Anger camera imaging technology has become widely popular for neutron diffraction imaging due to recent shortages in Helium-3 (He-3). Research into neutron diffraction optimized Anger camera by the Oak Ridge National Laboratory (ORNL) detectors group has provided an alternative to He-3 Tube-based detectors with a high-resolution Anger camera. However, the cost of these high-resolution Anger camera technology can make it less attractive than He-3 tubes when a large Field of View (FOV) is desired. Currently, there is a need for a lower-cost alternative to this high-resolution anger camera. Further applications for Anger camera have become of interest with the advent …

Development Of Arduino-Based Portable Systems For Electroanalytical Detection, Jiamei Huang

Masters Theses

This work presents the development of a multi-mode electroanalytical detection system based on Arduino microcontroller board. First, a multichannel impedance readout system is designed for alternating current electrokinetics (ACEK) based capacitive sensing. ACEK phenomena on 100μm interdigitated electrodes are observed via fluorescent particles as well as bioparticles, which illustrate the mechanisms of ACEK target enrichment for the capacitive sensing method. I2C multiplexer is applied to allow multiple impedance converters to work together providing continuous AC signals for ACEK capacitive sensing. Second, an electronic nose composed of three modules including a gas sensor array, a circuit for signal acquisition integrated with …

Non-Contact Vital Sign Detection Using Mm-Wave Radar, Marvin Joshi

Masters Theses

Vital Sign detection using radars has been a rising technology in the fields of healthcare, security, and military purposes. Typically, radars used for these tasks operate at lower frequencies due to their low cost and and the ability to detect behind obstacles, such as walls or undre debris. However, this leads to an overall large system as the lower the frequency of operation, the larger the size of the antennas. The system size increases when multiple antennas are used for subject localization. But, with the development of millimeter- wave radars and Antenna-on-Package (AoP) solutions, a more compact and portable radar …

Planar Ultra-Wideband Modular Antenna (Puma) Arrays For High-Volume Manufacturing On Organic Laminates And Bga Interfaces, James R. Lacroix

Masters Theses

This work proposes wideband and broadband Planar Ultra-wideband Modular Antenna (PUMA) arrays designed to improve cost and reliability for high production volume commercial and military applications. The designs feature simplified PCB stack-ups with high dielectric constant (Dk) dimensionally stable materials to improve the manufacturing cost and yield. Additionally, the packages use ball grid array (BGA) interconnects, commonly used in digital electronics, for simple solder reflow integration with radio frequency (RF) electronics. While high Dk materials present practical manufacturing benefits, theoretical background will show how and why PUMA arrays lose frequency bandwidth and scan volume with high Dk materials. Further, a …