Engineering Commons^™

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 …

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 …

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 …

Correcting For Terrain Interference, Attenuation, And System Bias For A Dual Polarimetric, X-Band Radar, Casey Wolsieffer

Masters Theses

This thesis outlines the procedure and theory used to calibrate the UMass eXperimental X-band Radar (UMAXX) for the purpose of monitoring meteorological events in the Pioneer Valley region. Due to the complex topography of the area, lower tilt angles are subject to partial or full beam blockage as well as ground clutter observed through the main beam or sidelobes. Additionally, there are biases internal and external to the system that impact the reflectivity and differential reflectivity measurements. These biases and corrections are addressed in this work. As the radar has been operational since September of 2018, there is ample data …

Camera-Based Remote Photoplethysmography For Estimation Of Heart Rate Using Single Board Computers, Benjamin Sweely

Masters Theses

The objective of this project was to develop a wireless, noncontact monitoring system that measures multiple physiological parameters in human faces from a distance using a camera. Compared to traditional sensors, this monitoring system does not use wires or adhesives, providing a safer, more user-friendly application. The goal of the monitoring systems was to estimate heart rate (HR). The current practices of measuring HR involve collecting electrocardiogram (ECG) signals from adhesive electrodes placed on various parts of the body and using a pulse oximeter (PO) typically placed on the ear lobe or finger. We were able to successfully create 2 …

Compressive Parameter Estimation Via Approximate Message Passing, Shermin Hamzehei

Masters Theses

The literature on compressive parameter estimation has been mostly focused on the use of sparsity dictionaries that encode a discretized sampling of the parameter space; these dictionaries, however, suffer from coherence issues that must be controlled for successful estimation. To bypass such issues with discretization, we propose the use of statistical parameter estimation methods within the Approximate Message Passing (AMP) algorithm for signal recovery. Our method leverages the recently proposed use of custom denoisers in place of the usual thresholding steps (which act as denoisers for sparse signals) in AMP. We introduce the design of analog denoisers that are based …

Radio Direction Finding Using Pseudo-Doppler For Uav-Based Animal Tracking, Anup Karki

Masters Theses

Radio Direction Finding (RDF) is commonly used for low cost tracking and navigation systems. However, for a low cost application and mobility, the design constraints are highly limited. Pseudo Doppler (PD) can improve RDF capabilities without being cost prohibitive. This work entails the analysis of PD RDF and its potential use for Unmanned Aerial Vehicles (UAV) that are currently employed in wildlife research animal tracking. PD is based on the doppler effect or doppler shift. The doppler effect works like a frequency modulator that increases or decreases the observed frequency depending on whether a signal source is approaching or receding …

The Umass Experimental X-Band Radar (Umaxx): An Upgrade Of The Casa Ma-1 To Support Cross-Polarization Measurements, Jezabel Vilardell Sanchez

Masters Theses

Ground-based radars are instruments commonly used to surveil the precipitation climate of the surrounding areas. Weather events are characterized by collecting backscatter data and analyzing computed products such as the Reflectivity Factor, the Doppler Velocity, the Spectrum Width, the Differential Reflectivity, the Co-polar Correlation Coefficient and the Differential Propagation Phase. The ability of the radar to transmit different polarization waves, such as horizontal and vertical polarization, allow for further analysis of the weather given the capability to perform co-polar and cross-polar measurements. The Linear Depolarization Ratio is another computed product based on the difference in power between the co-polarized and …

Insar Simulations For Swot And Dual Frequency Processing For Topographic Measurements, Gerard Masalias Huguet

Masters Theses

In Earth remote sensing precise characterization of the backscatter coefficient is important to extract valuable information about the observed target. A system that eliminates platform motion during near-nadir airborne observations is presented in this thesis, showing an improvement on the accuracy of measurements for a Ka- band scatterometer previously developed at Microwave Remote Sensing Laboratory (MIRSL). These very same results are used to simulate the reflectivity of such targets as seen from a spaceborne radar and estimate height errors based on mission-specific geometry. Finally, data collected from a dual-frequency airborne interferometer com- prised by the Ka-band system and an S-band …

Analog Computing Using 1t1r Crossbar Arrays, Yunning Li

Masters Theses

Memristor is a novel passive electronic device and a promising candidate for new generation non-volatile memory and analog computing. Analog computing based on memristors has been explored in this study. Due to the lack of commercial electrical testing instruments for those emerging devices and crossbar arrays, we have designed and built testing circuits to implement analog and parallel computing operations. With the setup developed in this study, we have successfully demonstrated image processing functions utilizing large memristor crossbar arrays. We further designed and experimentally demonstrated the first memristor based field programmable analog array (FPAA), which was successfully configured for audio …

Kasi: A Ka-Band And S-Band Cross-Track Interferometer, Gerard Ruiz Carregal

Masters Theses

A dual-frequency system is needed to better understand natural processes that constitute the environment and seasonal cycles of the Earth. A system working at two different wavelengths acquiring data simultaneously will give a valuable dataset since the conditions on the ground will be exactly the same. Hence, elements such as wind, soil moisture or any other changes on the ground will not interfere in the mea- surements. This thesis explains how an S-band radar was built and tested. Moreover, the experiments done with a Ka-band radar used as a scatterometer are explained as well as the data processing and analysis. …

Explorations Into Machine Learning Techniques For Precipitation Nowcasting, Aditya Nagarajan

Masters Theses

Recent advances in cloud-based big-data technologies now makes data driven solutions feasible for increasing numbers of scientific computing applications. One such data driven solution approach is machine learning where patterns in large data sets are brought to the surface by finding complex mathematical relationships within the data. Nowcasting or short-term prediction of rainfall in a given region is an important problem in meteorology. In this thesis we explore the nowcasting problem through a data driven approach by formulating it as a machine learning problem.

State-of-the-art nowcasting systems today are based on numerical models which describe the physical processes leading to …

Time Domain Sar Processing With Gpus For Airborne Platforms, Dustin Lagoy

Masters Theses

A time-domain backprojection processor for airborne synthetic aperture radar (SAR) has been developed at the University of Massachusetts’ Microwave Remote Sensing Lab (MIRSL). The aim of this work is to produce a SAR processor capable of addressing the motion compensation issues faced by frequency-domain processing algorithms, in order to create well focused SAR imagery suitable for interferometry. The time-domain backprojection algorithm inherently compensates for non-linear platform motion, dependent on the availability of accurate measurements of the motion. The implementation must manage the relatively high computational burden of the backprojection algorithm, which is done using modern graphics processing units (GPUs), programmed …

Ultra-Low-Power Configurable Analog Signal Processor For Wireless Sensors, James Kelly Griffin

Masters Theses

The demand for on-chip low-power Complementary Metal Oxide Semiconductor (CMOS) analog signal processing has significantly increased in recent years. Digital signal processors continue to shrink in size as transistors half in size every two years. However, digital signal processors (DSP's) notoriously use more power than analog signal processors (APS's). This thesis presents a configurable analog signal processor (CASP) used for wireless sensors. This CASP contains a multitude of processing blocks include the following: low pass filter (LPF), high pass filter (HPF) integrator, differentiator, operational transconductance amplifier (OTA), rectifier with absolute value functionality, and multiplier. Each block uses current-mode processing and …

Wavelet-Based Non-Homogeneous Hidden Markov Chain Model For Hyperspectral Signature Classification, Siwei Feng

Masters Theses

Hyperspectral signature classification is a kind of quantitative analysis approach for hyperspectral imagery which performs detection and classification of the constituent materials at pixel level in the scene. The classification procedure can be operated directly on hyperspectral data or performed by using some features extracted from corresponding hyperspectral signatures containing information like signature energy or shape. In this paper, we describe a technique that applies non-homogeneous hidden Markov chain (NHMC) models to hyperspectral signature classification. The basic idea is to use statistical models (NHMC models) to characterize wavelet coefficients which capture the spectrum structural information at multiple levels. Experimental results …

Propagation Prediction Over Random Rough Surface By Zeroth Order Induced Current Density, Narayana Srinivasan Balu

Masters Theses

Electromagnetic wave propagation over random sea surfaces is a classical problem of interest for the Navy, and significant research has been done over the years. Here we make use of numerical and analytical methods to predict the propagation of microwaves over random rough surface. The numerical approach involves utilization of the direct solution (using Volterra integral equation of the second kind) to currents induced on a rough surface due to forward propagating waves to compute the scattered field. The mean scattered field is computed using the Monte-Carlo method. Since the exact solution (consisting of an infinite series) to induced current …

Statistical Analysis Of Disturbances In Power Transmission Systems, Liu Liu

Masters Theses

Disturbance analysis is essential to the study of the power transmission systems. Traditionally, disturbances are described as megawatt (MW) events, but the access to data is inefficient due to the slow installation and authorization process of the monitoring device. In this paper, we propose a novel approach to disturbance analysis conducted at the distribution level by exploiting the frequency recordings from Frequency Disturbance Recorders (FDRs) of the Frequency Monitoring Network (FNET/GridEye), based on the relationship between frequency change and the power loss of disturbances - linearly associated by the Frequency Response. We first analyze the real disturbance records of North …

Improved Forensic Medical Device Security Through Eating Detection, Nathan Lee Henry

Masters Theses

Patients are increasingly reliant on implantable medical device systems today. For patients with diabetes, an implantable insulin pump system or artificial pancreas can greatly improve quality of life. As with any device, these devices can and do suffer from software and hardware issues, often reported as a safety event. For a forensic investigator, a safety event is indistinguishable from a potential security event. In this thesis, we show a new sensor system that can be transparently integrated into existing and future electronic diabetes therapy systems while providing additional forensic data to help distinguish between safety and security events. We demonstrate …

A Novel Authentication Method Using Multi-Factor Eye Gaze, Lucas A. Herrera

Masters Theses

A method for novel, rapid and robust one-step multi-factor authentication of a user is presented, employing multi-factor eye gaze. The mobile environment presents challenges that render the conventional password model obsolete. The primary goal is to offer an authentication method that competitively replaces the password, while offering improved security and usability. This method and apparatus combine the smooth operation of biometric authentication with the protection of knowledge based authentication to robustly authenticate a user and secure information on a mobile device in a manner that is easily used and requires no external hardware. This work demonstrates a solution comprised of …

Novel Applications For Phasor Measurement Units And Synchrophasor Data, Bradley Kerwin Greene

Masters Theses

The last decade has seen an intensified effort towards an improved, technologically advanced electric grid. This effort is largely in part to the need for cleaner and renewable sources of energy. Another motivator for this “smarter grid” is the need for a more reliable and efficiently operated of the wide scale electric infrastructure. The impact of these changes can expect to be seen at both the transmission and distribution level. At the transmission level phasor measurement units and synchrophasor data has emerged as one of the most enabling technologies for the smart grid movement. These devices measure and time synchronize, …

Design, Implementation, And Analysis Of A Time Of Arrival Measurement System For Rotating Machinery, Bryan Will Hayes

Masters Theses

The Non-contact Stress Measurement System (NSMS) acquires critical time of arrival data from multiple optical probes viewing a rotating piece of machinery, such as blades on a turbine engine rotor. The signal from each probe must be converted from light energy to an electrical signal, conditioned, and timed by a high speed counter to measure the time of arrival of the rotating machinery. This thesis describes, in detail, the design and analysis of the photo-detector electronics, analog signal conditioning electronics, and the timing electronics utilized in measuring the time of arrival. To measure the time of arrival with precision, the …

Block Level Link Path Design And Multilayer Via Transition Model Assembly Using S-Parameters, Francesco De Paulis

Masters Theses

"In high-speed data communication systems the complexity of link path between transmitters and receivers present a challenge for designers to maintain an acceptable bit error rate. An approach is presented in this thesis to design the link path on a block-by-block basis. The unique advantage of this approach lies on the physics-based model of each block, which then relates performance to geometry and makes design improvement and optimization possible. A tool based on the manipulation of frequency domain data has been designed to help in the design and analysis process of fast communication systems. It accepts as inputs the frequency …