Computer Engineering Commons^™

Understanding Quadrature Modulation By Designing A 7mhz Iq Test Bench To Encode The Polybius Square, William Lee Bradley

Dissertations and Theses

This thesis outlines the design of an IQ Test Bench that allows for experimentation of quadrature modulation techniques. Quadrature modulation utilizes two signals I and Q, 90° out of phase from each other, to greatly increase communication data rates. Using Desmos, a thorough mathematical analysis of waveform mixing is presented, and constellation diagrams are plotted from the results. From this an ancient fire signaling technique known as the Polybius Square is encoded into the system. The IQ Test Bench is built from fundamental components that would be contained within an RFFE: a local oscillator and two frequency mixers. The LO …

A Privacy-Preserving Strategy For The Trust Layer Of The Energy Grid Of Things Distributed Energy Resource Management System, Mohammed Abdullah Alsaid

Dissertations and Theses

Emergent from the shadows of the traditional grid flaws, the Smart Grid (SG) idea was born and led by government mandates toward cleaner energy production. The SG represents the next generation of electricity distribution systems that subsume recent technological innovations. It uses digital communication between its components and entities to attain more automation, self-sufficiency, and reliability. Unfortunately, this relatively new concept is not flawless; the intrinsic reliance on increased digital communication spreads open attack paths for adversaries. Therefore, finding solutions that address information exchange vulnerabilities has become imperative.

The Energy Grid of Things (EGoT) is Portland State University's implementation of …

Poster: Indoor Navigation For Visually Impaired People With Vertex Colored Graphs, Pei Du, Nirupama Bulusu

Electrical and Computer Engineering Faculty Publications and Presentations

Visually impaired people face many daily encumbrances. Traditional visual enhancements do not suffice to navigate indoor environments. In this paper, we explore path finding algorithms such as Dijkstra and A* combined with graph coloring to find a safest and shortest path for visual impaired people to navigate indoors. Our mobile application is based on a database which stores the locations of several spots in the building and their corresponding label. Visual impaired people select the start and destination when they want to find their way, and our mobile application will show the appropriate path which guarantees their safety.

Privacy-Preserving Information Security For The Energy Grid Of Things, Mohammed Alsaid, Nirupama Bulusu, Abdullah Bargouti, N. Sonali Fernando, John M. Acken, Tylor E. Slay, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

Smart grid infrastructure relies on information exchange between multiple actors in order to ensure system reliability. These actors include but are not limited to smart loads, grid control, and energy management technologies. As information exchange between these actors is susceptible to cyber-attacks, security and privacy issues are indispensable to ensure a reliable and stable grid. This position paper proposes a privacy-preserving, trust-augmented secure scheme for a smart grid implementation.

A Graph-Based Approach To Boundary Estimation With Mobile Sensors, Sean Onufer Stalley, Dingyu Wang, Gautam Dasarathy, John Lipor

Electrical and Computer Engineering Faculty Publications and Presentations

We consider the problem of adaptive sampling for boundary estimation, where the goal is to identify the two dimensional spatial extent of a phenomenon of interest. Motivated by applications in estimating the spread of wildfires with a mobile sensor, we present a novel graph-based algorithm that is efficient in both the number of samples taken and the distance traveled. The key idea behind our approach is that by sampling locations close to known cut edges (edges whose vertices lie on opposite sides of the boundary), we can reliably find additional cut edges. Our approach repeats this process of using the …

Modeling The Effect Of The Covid-19 Pandemic On Azithromycin Prescription In General Practices Across The Uk, Oluwasegun Isaac Daramola

altREU Projects

In the early months of the COVID-19 pandemic, it was reported that some antibiotics were prescribed as a remedy for viral treatment and prophylaxis based on non-randomized, uncontrolled short clinical trials. A major antibiotic consulted being Azithromycin; a broad-spectrum macrolide selected based on its immunomodulatory effects in chronic inflammatory lung diseases, with a seasonal prescription increase of 21.5% in March 2020 compared to March 2019.

To analyze the effect and possible antimicrobial resistance impact of the pandemic on Azithromycin prescription across general practices in the United Kingdom (UK), this study uses a time series decomposition modeling method to compare a …

Developing A Strategy For Creating Affordable Student Housing Solutions, Juan D. Campolargo

altREU Projects

College is becoming more and more expensive, and students are graduating with more and more debt. In 2021, we have almost 1.6 trillion dollars of student loan debt. While students are in college, they need a place to live, and this project will be about how to develop a strategy for creating affordable student housing solutions.

Housing should not be another cause of concern to students or really anyone.

The way it’s done is that people get more loans to pay for housing, or they work as much as they can when they’re not studying to pay for rent. Affordable …

Flight Simulator Modeling Using Recurrent Neural Networks, Nickolas Sabatini, Andreas Natsis

Undergraduate Research & Mentoring Program

Recurrent neural networks (RNNs) are a form of machine learning used to predict future values. This project uses RNNs tor predict future values for a flight simulator. Coded in Python using the Keras library, the model demonstrates training loss and validation loss, referring to the error when training the model.

From Inductive To Deductive Learning, Mikhail Mayers, Brian Henson

Undergraduate Research & Mentoring Program

Using Machine Vision as a way to give information to Prolog. Using Prolog to solve deductive problems and analogical problems without having to manually enter all facts and information.

Audio Beat Detection With Application To Robot Drumming, Michael James Engstrom

Dissertations and Theses

This Drumming Robot thesis demonstrates the design of a robot which can play drums in rhythm to an external audio source. The audio source can be either a pre-recorded .wav file or a live sample .wav file from a microphone. The dominant beats-per-minute (BPM) of the audio would be extracted and the robot would drum in time to the BPM. A Fourier Analysis-based BPM detection algorithm, developed by Eric Scheirer (Tempo and beat analysis of acoustical musical signals)ⁱ was adopted and implemented. In contrast to other popular algorithms, the main advantage of Scheirer's algorithm is it has …

A Resource Constrained Shortest Paths Approach To Reducing Personal Pollution Exposure, Elling Payne

REU Final Reports

As wildfires surge in frequency and impact in the Pacific Northwest, in tandem with increasingly traffic-choked roads, personal exposure to harmful airborne pollutants is a rising concern. Particularly at risk are school-age children, especially those living in disadvantaged communities near major motorways and industrial centers. Many of these children must walk to school, and the choice of route can effect exposure. Route-planning applications and frameworks utilizing computational shortest paths methods have been proposed which consider personal exposure with reasonable success, but few have focused on pollution exposure, and all have been limited in scalability or geographic scope. This paper addresses …

An Exploration Of Software Defined Radio And Gnu Radio Companion For Use In Drone-To-Drone Communication, Amanda K. H. Voegtlin

Undergraduate Research & Mentoring Program

In a world that increasingly relies on automation and intelligent robotics, there is a need for drones to expand their independence and adaptability in navigating their environments. One approach to this problem is the use of wireless communication between units in order to coordinate their sensor data and build real-time maps of the environments they are navigating. However, especially indoors, relying on a fixed transmission tower to provide data to the units faces connectivity challenges.

The purpose of this research was to determine the fitness of an on-drone assembly that uses the the NI B200mini software-defined radio board and Gnu …

Improvement Of 802.11 Protocol On Fully Programmable Wireless Radio, Eunji Lee

Undergraduate Research & Mentoring Program

The growth in the number of connected device usage has led to a rapidly increased data traffic on wireless network and the demand for access to high speed and stable Internet connection is becoming more prominent. However, current off the shelf wireless cards are not programmable or observable across layers of the standard protocol stack, which leads to poor practical performance. Thus, Wireless Open Access Research Platform (WARP), a scalable wireless platform providing programmable functionality at every layer of the network stack, has been used for the real-time implementation and improvement of 802.11 protocol.

An Analysis Of Lora Low Power Technology And Its Applications, Gomathy Venkata Krishnan

Undergraduate Research & Mentoring Program

The number of Internet of Things (IoT) devices has exponentially increased in the last decade. With the increase in these devices, there is a necessity to effectively connect and control these devices remotely. Cellular technologies cannot handle this demand since they are not cost effective and easy to deploy. This is where LoRa technology comes handy. LoRa is long-range, low-power, low cost technology that supports internet of things applications. LoRa has many advantages in terms of capacity, mobility, battery lifetime and cost. It uses the unlicensed 915MHz ISM band and can be easily deployed.

This research is focused on setting …

Biochemical Reservoir Computing, Hoang Nguyen, Christof Teuscher

Student Research Symposium

Reservoir computing is an emerging machine learning paradigm. Compared to traditional feedforward neural networks, the reservoir can be unstructured and recurrent and only the output layer is trained. Reservoirs can be built with various types of physical components, yet, biochemical building blocks have not been widely used. This project focuses on designing and testing a reservoir computer (RC) based on chemical reaction network (CRN). We simulated high-level CRNs in MATLAB and their complex chemical dynamics were observed over time. A CRN constructed by a network of coupled deoxyribozyme oscillators was chosen for the final RC model. The inputs of the …

Radiation Source Localization By Using Backpropagation Neural Network, Jian Meng, Christof Teuscher, Walt Woods

Student Research Symposium

The most difficult part of the radiation localization is that we cannot use the traditional acoustic localization method to determine where the radiation source is. It’s mainly because the electromagnetic waves are totally different with the sound wave. From the expression of the radioactive intensity, we can tell that the intensity of radiation not only depend on the distance from the radiation but also related to the type of the nuclide. In general, the relationship between the intensity and the distance satisfy the inverse-square law, which is a non-linear relationship. In other words, if we can use the measurement and …

Silicon Compilation And Test For Dataflow Implementations In Gasp And Click, Swetha Mettala Gilla

Dissertations and Theses

Many modern computer systems are distributed over space. Well-known examples are the Internet of Things and IBM's TrueNorth for deep learning applications. At the Asynchronous Research Center (ARC) at Portland State University we build distributed hardware systems using self-timed computation and delay-insensitive communication. Where appropriate, self-timed hardware operations can reduce average and peak power, energy, latency, and electromagnetic interference. Alternatively, self-timed operations can increase throughput, tolerance to delay variations, scalability, and manufacturability.

The design of complex hardware systems requires design automation and support for test, debug, and product characterization.

This thesis focuses on design compilation and test support for dataflow …

Proving Non-Deterministic Computations In Agda, Sergio Antoy, Michael Hanus, Steven Libby

Computer Science Faculty Publications and Presentations

We investigate proving properties of Curry programs using Agda. First, we address the functional correctness of Curry functions that, apart from some syntactic and semantic differences, are in the intersection of the two languages. Second, we use Agda to model non-deterministic functions with two distinct and competitive approaches incorporating the non-determinism. The first approach eliminates non-determinism by considering the set of all non-deterministic values produced by an application. The second approach encodes every non-deterministic choice that the application could perform. We consider our initial experiment a success. Although proving properties of programs is a notoriously difficult task, the functional logic …

A Backend Framework For The Efficient Management Of Power System Measurements, Benjamin Mccamish, Rich Meier, Jordan Landford, Robert B. Bass, David Chiu, Eduardo Cotilla-Sanchez

Electrical and Computer Engineering Faculty Publications and Presentations

Increased adoption and deployment of phasor measurement units (PMU) has provided valuable fine-grained data over the grid. Analysis over these data can provide insight into the health of the grid, thereby improving control over operations. Realizing this data-driven control, however, requires validating, processing and storing massive amounts of PMU data. This paper describes a PMU data management system that supports input from multiple PMU data streams, features an event-detection algorithm, and provides an efficient method for retrieving archival data. The event-detection algorithm rapidly correlates multiple PMU data streams, providing details on events occurring within the power system. The event-detection algorithm …

Formal Modeling And Verification Of Delay-Insensitive Circuits, Hoon Park

Dissertations and Theses

Einstein's relativity theory tells us that the notion of simultaneity can only be approximated for events distributed over space. As a result, the use of asynchronous techniques is unavoidable in systems larger than a certain physical size. Traditional design techniques that use global clocks face this barrier of scale already within the space of a modern microprocessor chip. The most common response by the chip industry for overcoming this barrier is to use Globally Asynchronous Locally Synchronous (GALS) design techniques. The circuits investigated in this thesis can be viewed as examples of GALS design. To make such designs trustworthy it …

From Boolean Equalities To Constraints, Sergio Antoy, Michael Hanus

Computer Science Faculty Publications and Presentations

Although functional as well as logic languages use equality to discriminate between logically different cases, the operational meaning of equality is different in such languages. Functional languages reduce equational expressions to their Boolean values, True or False, logic languages use unification to check the validity only and fail otherwise. Consequently, the language Curry, which amalgamates functional and logic programming features, offers two kinds of equational expressions so that the programmer has to distinguish between these uses. We show that this distinction can be avoided by providing an analysis and transformation method that automatically selects the appropriate operation. Without this distinction …

Compiling Collapsing Rules In Certain Constructor Systems, Sergio Antoy, Andy Jost

Computer Science Faculty Publications and Presentations

The implementation of functional logic languages by means of graph rewriting requires a special handling of collapsing rules. Recent advances about the notion of a needed step in some constructor systems offer a new approach to this problem. We present two results: a transformation of a certain class of constructor-based rewrite systems that eliminates collapsing rules, and a rewrite-like relation that takes advantage of the absence of collapsing rules. We formally state and prove the correctness of these results. When used together, these results simplify without any loss of efficiency an implementation of graph rewriting and consequently of functional logic …

Semi-Modular Delay Model Revisited In Context Of Relative Timing, Hoon Park, Anping He, Marly Roncken, Xiaoyu Song

Electrical and Computer Engineering Faculty Publications and Presentations

A new definition of semi-modularity to accommodate relative timing constraints in self-timed circuits is presented. While previous definitions ignore such constraints, the new definition takes them into account. The difference on a design solution for a well-known speed-independent circuit implementation of the Muller C element and a set of relative timing constraints that renders the implementation hazard free is illustrated. The old definition produces a false semi-modularity conflict that cannot exist due to the set of imposed constraints. The new definition correctly accepts the solution.

Modular Timing Constraints For Delay-Insensitive Systems, Hoon Park, Anping He, Marly Roncken, Xiaoyu Song, Ivan Sutherland

Electrical and Computer Engineering Faculty Publications and Presentations

This paper introduces ARCtimer, a framework for modeling, generating, verifying, and enforcing timing constraints for individual self-timed handshake components. The constraints guarantee that the component’s gate-level circuit implementation obeys the component’s handshake protocol specification. Because the handshake protocols are delayinsensitive, self-timed systems built using ARCtimer-verified components are also delay-insensitive. By carefully considering time locally, we can ignore time globally. ARCtimer comes early in the design process as part of building a library of verified components for later system use. The library also stores static timing analysis (STA) code to validate and enforce the component’s constraints in any self-timed system built …

Detection Of Variable Retention Time In Dram, Neraj Kumar

Dissertations and Theses

This thesis investigates a test method to detect the presence of Variable Retention Time (VRT) bits in manufactured DRAM. The VRT bits retention time is modeled as a 2-state random telegraph process that includes miscorrelation between test and use. The VRT defect is particularly sensitive to test and use conditions. A new test method is proposed to screen the VRT bits by simulating the use conditions during manufacturing test. Evaluation of the proposed test method required a bit-level VRT model to be parameterized as a function of temperature and voltage conditions. The complete 2-state VRT bit model combines models for …

A Comparative Study Of Reservoir Computing For Temporal Signal Processing, Alireza Goudarzi, Peter Banda, Matthew R. Lakin, Christof Teuscher, Darko Stefanovic

Computer Science Faculty Publications and Presentations

Reservoir computing (RC) is a novel approach to time series prediction using recurrent neural networks. In RC, an input signal perturbs the intrinsic dynamics of a medium called a reservoir. A readout layer is then trained to reconstruct a target output from the reservoir's state. The multitude of RC architectures and evaluation metrics poses a challenge to both practitioners and theorists who study the task-solving performance and computational power of RC. In addition, in contrast to traditional computation models, the reservoir is a dynamical system in which computation and memory are inseparable, and therefore hard to analyze. Here, we compare …

Self-Timed Dram Data Interface, Rajesh Nerkar

Dissertations and Theses

A DRAM communicates with a processing unit via two interfaces: a data interface and a command interface. In today's DRAMs, also known as synchronous DRAMs (SDRAMs), both interfaces use a clock to communicate with the processing unit. The clock times the communication between the processing unit and the SDRAM on both the data interface and the command interface.

We propose a self-timed DRAM. The self-timed DRAM introduces more flexibility into the DRAM interface by eliminating the clock. The command interface and the data interface each communicate with the processing unit using a handshake protocol rather than a clock.

This thesis …

A Quantitative Analysis Of Memory Controller Page Policies, Matthew Blackmore

Dissertations and Theses

Two common goals in computing system design are increasing performance and decreasing power consumption. DRAM-based memory subsystems are a major component of both system performance and power consumption. Memory controllers employ strategies to efficiently schedule DRAM operations to reduce latency and to utilize DRAM low power modes when possible. One of the most important of these is the page policy, which determines when to close pages in DRAM. An effective DRAM memory controller page policy is important to minimizing power consumption and increasing system performance. This thesis explores the impact memory controller page policy has on performance as measured by …

Optimal Network Topologies And Resource Mappings For Heterogeneous Networks-On-Chip, Haera Chung

Dissertations and Theses

Communication has become a bottleneck for modern microprocessors and multi-core chips because metal wires don't scale. The problem becomes worse as the number of components increases and chips become bigger. Traditional Systems-on-Chips (SoCs) interconnect architectures are based on shared-bus communication, which can carry only one communication transaction at a time. This limits the communication bandwidth and scalability. Networks-on-Chip (NoC) were proposed as a promising solution for designing large and complex SoCs. The NoC paradigm provides better scalability and reusability for future SoCs, however, long-distance multi-hop communication through traditional metal wires suffers from both high latency and power consumption. A radical …

Measurement And Modeling Of Passive Surface Mount Devices On Fr4 Substrates, Rahulkumar Sadanand Koche

Dissertations and Theses

Passive components like resistors, capacitors and inductors are used in every electronic system. These are the very basic components which affect the system performance at higher frequencies and it is necessary to understand and model the behavior of these components in a very accurate manner. This work focuses on utilizing Printed Circuit Board (PCB) test boards, or fixtures, made of FR4 for characterizing Surface Mount Device (SMD) components. Agilent's Advanced Design System (ADS) microwave circuit simulation software was used for designing the microstrip transmission lines as well as for generating the layout for manufacturing of the PCB. SMD resistors, capacitors …