VLSI and Circuits, Embedded and Hardware Systems Commons^™

Amplification In Mems Rlc Circuits For Enhanced Sensitivity And Mems Applications, Mutaz Mohd Hamdi Al Fayad

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Micro-electro-mechanical systems (MEMS) have garnered significant attention due to their unique characteristics, including small size, high sensitivity, and cost-effective mass production. While electrostatic actuation offers low power consumption, it requires high voltage to move the MEMS structure, posing a challenge for applications such as RF switches and MEMS resonator-based sensors. Reducing the required input voltage for electrostatic MEMS remains a key research focus.

This thesis investigates voltage amplification in electrostatic MEMS through integration with resonant RLC circuits. By leveraging resonance, optimized configurations are designed to maximize voltage gain and enhance the signal-to-noise ratio. Through theoretical modeling and simulations using MATLAB …

Applying Circuit Theory To Describe Changes In Structural Landscape Connectivity In Response To Wildfire, Christian Ross Nielsen

School of Natural Resources: Dissertations, Theses, and Student Research

Understanding and conserving ecological connectivity is critical to the preservation of vulnerable landscapes. Circuit theory, in which landscapes are imagined as circuit boards with varying resistances to the flow of current, is being increasingly used to model spatially explicit connectivity of landscapes and to inform land management and conservation decision-making. Utilizing continuous, quantitative estimates of percent cover by five land cover functional groups to create a conductance surface, this study expanded upon an established application of circuit theory that used the open-source software Circuitscape to model species-agnostic, omnidirectional connectivity. This model was automated using Python to create time-series connectivity maps …

Development Of A Multi-Use Modular Microfluidic Platform Using 3d Printing, Carson Emeigh

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Microfluidic lab-on-a-chip (LoC) technology has driven numerous innovations due to their ability to perform laboratory-scale experiments on a single chip using microchannels. Although LoC technology has been innovative, it still suffers from limitations related to its fabrication and design flexibility. Typical LoC fabrication, with photolithography, is time consuming, expensive, and inflexible. To overcome the limitations of LoC devices, modular microfluidic platforms have been developed where multiple microfluidic modules, each with a specific function or group of functions, can be combined on a single platform. Modular microfluidics have overcome some of the limitations of LoC devices, but currently, their fabrication is …

Low-Power, Event-Driven System On A Chip For Charge Pulse Processing Applications, Joseph A. Schmitz

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

This dissertation presents an electronic architecture and methodology capable of processing charge pulses generated by a range of sensors, including radiation detectors and tactile synthetic skin. These sensors output a charge signal proportional to the input stimulus, which is processed electronically in both the analog and digital domains. The presented work implements this functionality using an event-driven methodology, which greatly reduces power consumption compared to standard implementations. This enables new application areas that require a long operating time or compact physical dimensions, which would not otherwise be possible. The architecture is designed, fabricated, and tested in the aforementioned applications to …

Creating An Automatic Lowering Function For Quarter-Scale Tractor Pulling Sled, Sam Wilkins

Honors Program: Senior Projects (Public)

As the agricultural industry works to continuously integrate innovative technology and improve production efficiency, improved on-board data acquisition and transmission will be necessary for all agricultural machines. To make this a reality, the utilization of controller area network (CAN) technology will be crucial. Therefore, it is important for all agricultural engineers to have foundational knowledge of CAN bus systems and the standards that govern their use in industry. The UNL quarter-scale tractor team regularly utilizes CAN buses on their tractors and testing equipment. One such testing machine is the team’s pulling sled, which uses CAN messages to transport important information …

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 …

Low Power Multi-Channel Interface For Charge Based Tactile Sensors, Samuel Hansen

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

Analog front end electronics are designed in 65 nm CMOS technology to process charge pulses arriving from a tactile sensor array. This is accomplished through the use of charge sensitive amplifiers and discrete time filters with tunable clock signals located in each of the analog front ends. Sensors were emulated using Gaussian pulses during simulation. The digital side of the system uses SAR (successive approximation register) ADCs for sampling of the processed sensor signals.

Adviser: Sina Balkır

Asic Design To Support Low Power High Voltage Power Supply For Radiation Monitoring Applications, Daniel Rogge

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

A low power high voltage power supply is designed for use in a long duration radiation monitoring system. The supply employs a flexible pulse frequency modulation switching controller implemented in a 0.35 $\mu$m CMOS technology. The controller drives and regulates a flyback transformer driven 12-stage Cockroft-Walton voltage multiplier chain. The chain provides bias for the dynodes of a photomultiplier tube. The supply voltage is selectable via a 12-bit on-chip digital to analog converter. The system is designed for low power operation and immunity to supply voltage variation as the application is battery-powered.

Advisors: Sina Balkir and Michael W. Hoffman

Cmos Radioactive Isotope Identification With Multichannel Analyzer And Embedded Neural Network, Samuel Murray

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

A radiation detection and identification system is designed and implemented to perform gamma ray spectroscopy on radioactive sources and identify which isotopes are present in the sources. A multichannel analyzer is implemented on an ASIC to process the signal produced from gamma rays detected by a scintillator and photomultiplier tube and to quantize the gamma ray energies to build a histogram. A fast, low memory embedded neural network is implemented on a microcontroller ASIC to identify the isotopes present in the gamma ray histogram produced by the multichannel analyzer in real time.

Advisors: Sina Balkir and Michael W. Hoffman

Comparing Various Hardware/Software Solutions And Conversion Methods For Controller Area Network (Can) Bus Data Collection, Samuel E. Marx, Joe D. Luck, Santosh Pitla, Roger M. Hoy

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Various hardware and software solutions exist for collecting Controller Area Network (CAN) bus data. Digital data accuracy could vary based upon different data logging methods (e.g., hardware/software timing, processor timing, etc.). CAN bus data were collected from agricultural tractors using multiple data acquisition solutions to quantify differences among collection methods and demonstrate potential data accumulation rates. Two types of data were observed for this study. The first, CAN bus frame data, represents data collected for each line of hex data sent from an ECU. One issue with frame data is the resulting large file sizes, therefore a second logging format …

Low-Power Analog Processing, Daniel J. White

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

This dissertation presents the analog harmonic transform (AHT) and a first implementation in an integrated circuit. The transform is designed for a regular and simple hardware structure. It provides coefficients relating to an input signal's spectrum. These coefficients also have a simple relationship to the signal's Fouri\'er series coefficients.

The AHT is defined in its ideal form and evaluated for two example signal classification applications. Both military vehicle and bearing fault classification tasks are presented which validate the ability of a neural network to use the AHT coefficients to correctly classify the input signals. Because any real use of the …

Cmos Smart Camera With Focal Plane Neighborhood-Parallel Image Processing, Joseph A. Schmitz

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

A neighbhorhood-based smart camera architecture is designed and implemented in a 0.13 μm CMOS technology. Each 8 × 8 region of pixels contains a small processor with local memory, which are tiled to form a full-resolution camera. Each processor operates in parallel, enabling high-speed image processing suitable for tracking and recognition tasks. The architecture features the programming flexibility of designs us- ing chip-level and row-level processors while preserving the scalability of pixel-parallel processing elements. The neighborhood processors are implemented physically be- tween the pixel photodiodes, creating multiple design challenges that are discussed in detail.

Advisors: Sina Balkir and Michael W. …

Physical Design Of A Smart Camera With Integrated Digital Pixel Sensors Using A 0.13Μm 8-Layer Metal Cmos Process, Mahir K. Gharzai

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

The design of cameras has historically kept imagery and computational circuitry isolated in an attempt to maximize image quality by improving pixel pitch and routing density. Although this technique has worked in creating high density arrays of pixels for large resolution imagers, it has never been able to achieve high framerate computational operations.

A radical approach is introduced to solve this dilemma by creating compact, low- power pixel elements with built-in analog-to-digital converters that directly interface with digital logic. These pixels are capable of integrating alongside logic cells and to create an array of pixels inside the processor that can …

An Rf Cmos Implementation Of An Adaptive Filter For Narrow-Band Interferer Suppression In Uwb Systems, Markus Both

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

Ultra-wideband (UWB) technology is a new type of technology for wireless communication that is based on the transmission of low power sub-nanosecond pulses. UWB communication utilizes a large bandwidth that overlaps and is coexistent with other wireless communication standards that can be also considered as narrow-band interferers. Because UWB systems are highly susceptible to narrow-band interferers, there is a demand for interferer suppression. An adaptive filter consisting of a two-element diversity receiver that performs minimum mean square error combining (MMSE) by the LMS algorithm is proposed. Thereby the elements of the LMS algorithm as well as the receiver LNA were …

A 2-D Processor Array For Massively Parallel Image Processing, Anantha Krishna Nelliparthi

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

The concept of introducing image processing logic within the spatial gaps of an array of photodiodes is the key factor behind the presented work. A two-dimensional massively parallel image processing paradigm based on 8X8 pixel neighborhood digital processors has been designed. A low complexity processor array architecture along with its instruction set has been designed and fully verified on a FPGA platform. Various image processing tests have been run on the FPGA platform to demonstrate the functionality of a design that uses 12 parallel processors. The test results indicate that the architecture is scalable to support high frame rates while …

Wireless Embedded Smart Cameras: Performance Analysis And Their Application To Fall Detection For Eldercare., Alvaro Pinto

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

Wireless Embedded Smart Camera Networks has received a lot of attention from academia and industry because they are small in size and easy to deploy, and they offer a multitude of attractive applications. They can be used for embedded single unit applications, or can be networked for multi-camera applications.

We first analyze three different operation scenarios for a wireless vision sensor network wherein different levels of local processing is performed. A detailed quantitative comparison of three operation scenarios are presented in terms of energy consumption and latency. This quantitative analysis provides the motivation for performing high-level local processing and decision …

A Single-Chip Ultra-Wideband Based Wireless Sensor Network Node, Nathan R. Schemm

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

This dissertation presents the design of a next-generation wireless sensor network node. The node incorporates many new and innovative technologies such as an ultra-wideband radio which allows very low-energy communication, a low-power radiation detection front end, and an efficient implementation of dynamic voltage scaling which improves the energy efficiency of the integrated processor. The complete design is integrated on a single chip for maximum power savings and minimal size.

The ultra-wideband transceiver includes many novel techniques to produce a receiver with low power consumption and fast and accurate packet acquisition and reception. These include the use of a standard symmetric …

Where Does Your Institution Stand?, Wendell Brase, Mark Askren

Information Technology Services: Publications

Media coverage of sustainability and "green" issues is hard to ignore these days. But less clear is a specific understanding of what this agenda means within higher ed IT organizations. For starters, it's useful to self-assess whether your campus is a leading innovator on all things "green" or satisfied to remain inconspicuous in the middle of the pack. If your institution is trailing but wants to assert a leadership role in environmental stewardship, you need to get engaged to understand what it will take to catch up and how IT can be a leader, not just a contributor, to such …