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Full-Text Articles in Signal Processing

A Software-Defined Radio Testbed For Mimo-Ofdm Communications, Chaz G. Maschman Apr 2026

A Software-Defined Radio Testbed For Mimo-Ofdm Communications, Chaz G. Maschman

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

In this thesis, we implement a testbed for multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems via GNU Radio. Specifically, we implement a configurable framework for the construction of MIMO-OFDM software-defined radio (SDR) systems as a GNU Radio module. The GNU Radio MIMO-OFDM module consists of multiple algorithmic blocks necessary for implementation of a MIMO-OFDM system. This includes a library for the generation of orthogonal or pseudo-random pilot sequences, amendments to the Schmidl-Cox protocol for MIMO synchronization, and the creation of click-and-drag GNU Radio blocks implementing the conversion of arbitrary data sent via external programs to MIMO-OFDM frames, the initial …


Scalability And Connectivity Challenges For The Future Of Digital Radio Communication, Christopher Bayliss May 2024

Scalability And Connectivity Challenges For The Future Of Digital Radio Communication, Christopher Bayliss

Honors Program: Senior Projects (Public)

This thesis explores future challenges in digital radio communication, particularly focusing on scalability and connectivity issues that could impede technological advancements. With the increasing production of digital technology and reliance on radio frequencies, there is a need for innovative solutions to overcome limitations in spectrum availability, interference management, and bandwidth constraints. This work evaluates current modulation techniques, spectrum allocation strategies, and advanced communication technologies such as cognitive radio systems and reconfigurable intelligent surfaces. Through a comprehensive literature review and analysis, this thesis identifies promising developments, including dynamic spectrum sharing and symbiotic radio systems, that could significantly enhance spectrum efficiency and …


Star-Based Reachability Analysis Of Binary Neural Networks On Continuous Input, Mykhailo Ivashchenko May 2024

Star-Based Reachability Analysis Of Binary Neural Networks On Continuous Input, Mykhailo Ivashchenko

School of Computing: Dissertations, Theses, and Student Research

Deep Neural Networks (DNNs) have become a popular instrument for solving various real-world problems. DNNs’ sophisticated structure allows them to learn complex representations and features. However, architecture specifics and floating-point number usage result in increased computational operations complexity. For this reason, a more lightweight type of neural networks is widely used when it comes to edge devices, such as microcomputers or microcontrollers – Binary Neural Networks (BNNs). Like other DNNs, BNNs are vulnerable to adversarial attacks; even a small perturbation to the input set may lead to an errant output. Unfortunately, only a few approaches have been proposed for verifying …


Dung Dkar Cloak: Exploring Soft Interfaces For Sonic Interactions, Judit Eszter Kárpáti, Esteban De La Torre Jan 2024

Dung Dkar Cloak: Exploring Soft Interfaces For Sonic Interactions, Judit Eszter Kárpáti, Esteban De La Torre

Textile Society of America: Symposium Proceedings

The importance of crossmodal interaction within the contemporary cultural, technological and scientific panorama has evidently gained significant attention due to its remarkable advantages in creating a meaningful, interwoven, and integrated experience. The use and recontextualization of textiles in such exploratory quest into the human senses has proven to be critical. Computational science, algorithmic logic and digital devices have always been rooted and closely interwoven with textile crafts and practices. Recent technological advancements have further combined technology and textile, generating interactive textile surfaces, constructing endless possibilities for multisensorial experiences. In this presentation we will examine how we can weave a sensitive …


Low-Power, Event-Driven System On A Chip For Charge Pulse Processing Applications, Joseph A. Schmitz Dec 2023

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 …


Low Power Multi-Channel Interface For Charge Based Tactile Sensors, Samuel Hansen Dec 2022

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


Real Time Audio Processing Using A Low-Power Digital Signal Processor, Aaron Norlinger May 2022

Real Time Audio Processing Using A Low-Power Digital Signal Processor, Aaron Norlinger

Honors Program: Senior Projects (Public)

This project focused on the creation of a series of audio processing functions that could run in real time on the ezDSP5502 processor. The Digital Signal Processor (DSP) being used for this project is an industry standard for lowpower signal processing applications. The overall goal was to have a code base that could sample audio in real time from any source, filter it in a variety of ways, run a Fast Fourier Transform on the audio, display the resulting frequency data to an LCD screen, and then output the filtered audio to an external speaker. This general process is used …


Design Of Hardware To Aid Smartphone-Based Oscilloscope App, Riddock Moran May 2022

Design Of Hardware To Aid Smartphone-Based Oscilloscope App, Riddock Moran

Honors Program: Senior Projects (Public)

A smartphone-based oscilloscope improves on traditional lab oscilloscopes in accessibility and portability but faces several performance limitations compared to traditional oscilloscopes. Among these, an oscilloscope app that uses the phone’s audio to read voltage signals will have a sampling rate and voltage bottlenecked by the capabilities of the audio codec, which will rarely exceed a rate of 48 kHz and 1 volt, respectively. Additionally, smartphones lack the ability to read line-in audio, allowing only one channel input through the microphone. Direct connections to an audio source may not be possible due to requiring an audio jack connection, and different poles …


Application-Aware Cognitive Multi-Hop Wireless Networking Testbed And Experiments, Trenton T. Evans Jul 2017

Application-Aware Cognitive Multi-Hop Wireless Networking Testbed And Experiments, Trenton T. Evans

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

In this thesis, we present a new architecture for application-aware cognitive multihop wireless networks (AC-MWN) with testbed implementations and experiments. Cognitive radio is a technique to adaptively use the spectrum so that the resource can be used more efficiently in a low cost way. Multihop wireless networks can be deployed quickly and flexibly without a fixed infrastructure. In presented new architecture, we study backbone routing schemes with network cognition, routing scheme with network coding and spectrum adaptation. A testbed is implemented to test the schemes for AC-MWN. In addition to basic measurements, we implement a video streaming application based on …


5g-Ucda Multi Antenna-To-Logical Cell Circular Fifo Mapping Strategy For High-Speed Train Wireless Communications, Subharthi Banerjee Apr 2017

5g-Ucda Multi Antenna-To-Logical Cell Circular Fifo Mapping Strategy For High-Speed Train Wireless Communications, Subharthi Banerjee

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

2020 is the target year for the roll out of fifth generation wireless communication methodologies. The commercial vendors have characterized 5G as a collection of disruptive set of technologies to provide high throughput, low latency communication supporting a variety of services, i.e., machine to machine communication to next generation base stations and vehicle-to-vehicle communication to radio-over-fiber and high mobility channels. High-speed train wireless communication channels as a subset of high mobility channels have their clear advantages and disadvantages considering other vehicular channels. The speed of high-speed trains is going to reach 500km/hr and with Hyperloop it may reach 1000km/hr. LTE …


2017 State Of Resnet Report Acuta/Acuho-1 Jan 2017

2017 State Of Resnet Report Acuta/Acuho-1

ACUTA: Other Publications

Copyright 2017 Association for College and University Technology Advancement & Association of College and University Housing Officers -International 2017


2016 Acuta/Acuho-1 State Of Resnet Report Jan 2016

2016 Acuta/Acuho-1 State Of Resnet Report

ACUTA: Other Publications

In This Issue

Introduction

Methodology

Executive Summary

Findings

Bandwidth Management

Wireless Coverage and Capacity

ResNet Service and Support

Planning and Measurement

Funding and Technology Costs

Outsourcing


Assessing Gait And Postural Stability Of Construction Workers Using Wearable Wireless Sensor Networks, Houtan Jebelli May 2015

Assessing Gait And Postural Stability Of Construction Workers Using Wearable Wireless Sensor Networks, Houtan Jebelli

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Falling accidents are a leading cause of fatal and nonfatal injuries in the construction industry. This fact demonstrates the need for a comprehensive fall-risk analysis that incorporates the effects of construction workers’ physiological characteristics. In this context, the objective of the thesis is to investigate and validate the usefulness of the gait- and postural-stability metrics in assessing construction workers’ fall risks. Diverse metrics that assess the capability to keep the body balanced and maintain coordination of body segments during locomotion (gait stability) and stationary postures (postural stability) have been introduced and used in clinical applications. However, their usefulness in the …


Energy Harvesting And Storage: The Catalyst To The Power Constraint For Leveraging Internet Of Things (Iot) On Trains, Kelechi Nwogu May 2015

Energy Harvesting And Storage: The Catalyst To The Power Constraint For Leveraging Internet Of Things (Iot) On Trains, Kelechi Nwogu

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

The success of Wireless Sensor Networks is heavily constrained by its reliance on storage technology like batteries, which are a finite resource. Whilst the number of transistors in an IC doubles every 18 months, the energy density of batteries is relatively flat during the same time period. This is a key challenge in leveraging the Internet of Things on trains.

The gravity of this problem is increased by an order of magnitude when the network is to be scaled up to hundreds or thousands of nodes. Comprehensive research and development efforts have been devoted to building ultra-low power sensors. These …


2015 Acuta/Nacubo/Acuho-1 Report Jan 2015

2015 Acuta/Nacubo/Acuho-1 Report

ACUTA: Other Publications

In This Issue

Introduction

Methodology

Executive Summary

Findings

Bandwidth Management

Wireless Coverage and Capacity

ResNet Service and Support

Planning and Measurement

Funding and Technology Costs

Outsourcing


A Study On Resource Efficient Digital Multimedia Security Measures In Mobile Devices, Prabhat Dahal Dec 2014

A Study On Resource Efficient Digital Multimedia Security Measures In Mobile Devices, Prabhat Dahal

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

Advanced image and video processing abilities in smart phones and digital cameras make them popular means to capture multimedia. In addition, the integration of internet into such devices users seek to capture and easily share multimedia right from their smartphone while most steganography techniques are computer based. Hence, it is of utmost importance that the multimedia be processed for steganography right within the devices for multimedia authentication.

In this thesis, we first implement steganography into mobile smart devices that can capture multimedia. For devices such as smart phones, we propose a method to hide payload bits within video frames. The …


Low-Power Analog Processing, Daniel J. White Nov 2014

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 …


Designing A Bayer Filter With Smooth Hue Transition Interpolation Using The Xilinx System Generator, Zhiqiang Li, Peter Revesz Nov 2014

Designing A Bayer Filter With Smooth Hue Transition Interpolation Using The Xilinx System Generator, Zhiqiang Li, Peter Revesz

School of Computing: Conference and Workshop Papers

This paper describes the design of a Bayer filter with smooth hue transition using the System Generator for DSP. We describe and compare experimentally two different designs, one based on a MATLAB implementation and the other based on a modification of the Bayer filter using bilinear interpolation.


2014 Acuta/Nacubo/Acuho-1 State Of Resnet Report Jan 2014

2014 Acuta/Nacubo/Acuho-1 State Of Resnet Report

ACUTA: Other Publications

In This Issue

Introduction

Methodology

Executive Summary

Findings

Bandwidth Management

Wireless Coverage

ResNet Management & Support

Planning & Measurement

Costs & Funding

Outsourcing


A Study On Countermeasures Against Steganography: An Active Warden Approach, Qilin Qi Dec 2013

A Study On Countermeasures Against Steganography: An Active Warden Approach, Qilin Qi

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

Digital steganography is a method used for hiding information in digital images. It can be used for secure communication. There have been many robust digital steganography methods invented in recent decades. The steganographic message can be inserted in multimedia cover signal such as audio, image and video. However, this technique also may be used by malicious users to transmit dangerous information through the Internet beyond the control of security agencies. How to detect and/or block potentially dangerous information transmission on the Internet through billions of multimedia files while not affecting innocent multimedia communications becomes a challenging problem. Existing steganalysis methods …


Individual Articulator's Contribution To Phoneme Production, Jun Wang, Jordan R. Green, Ashok Samal May 2013

Individual Articulator's Contribution To Phoneme Production, Jun Wang, Jordan R. Green, Ashok Samal

School of Computing: Conference and Workshop Papers

Speech sounds are the result of coordinated movements of individual articulators. Understanding each articulator’s role in speech is fundamental not only for understanding how speech is produced, but also for optimizing speech assessments and treatments. In this paper, we studied the individual contributions of six articulators, tongue tip, tongue blade, tongue body front, tongue body back, upper lip, and lower lip to phoneme classification. A total of 3,838 vowel and consonant production samples were collected from eleven native English speakers. The results of speech movement classification using a support vector machine indicated that the tongue encoded significantly more information than …


2013 Acuta/Nacubo State Of Resent Report Jan 2013

2013 Acuta/Nacubo State Of Resent Report

ACUTA: Other Publications

In This Issue

Introduction

Methodology

Executive Summary

Findings

Coverage & Bandwidth Demands

ResNet Management & Support

ResNet Costs & Funding

Alternative Models


Online Nonintrusive Condition Monitoring And Fault Detection For Wind Turbines, Xiang Gong Dec 2012

Online Nonintrusive Condition Monitoring And Fault Detection For Wind Turbines, Xiang Gong

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

The goal of this dissertation research is to develop online nonintrusive condition monitoring and fault detection methods for wind turbine generators (WTGs). The proposed methods use only the current measurements that have already been used by the control and protection systems of WTGs; no additional sensors or data acquisition devices are needed. Current-based condition monitoring and fault detection techniques have great economic benefits and the potential to be adopted by the wind energy industry. However, there are challenges in using current measurements for wind turbine condition monitoring and fault detection. First, it is a challenge to extract WTG fault signatures …


Energy Efficiency Analysis And Optimization On Mobile Video Wireless Delivery, Jianxin Sun Jul 2012

Energy Efficiency Analysis And Optimization On Mobile Video Wireless Delivery, Jianxin Sun

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

Micro-electronic industry has been boosting the capability of wireless mobile devices on full-scale. However, battery, as the only power source of most mobile devices, is experiencing a relatively slow development. Therefore, how to optimally utilize the limited battery energy on mobile devices under a predefined performance requirement becomes a critical issue. On the other hand, it is still unclear that how the battery capacity consumption is allocated on different working pattern of a specific video codec under various tempo-spatial scales and parameters, which has posed a design challenge on power management on multimedia communication system. Furthermore, an optimization method is …


Vision-Based Human Action Recognition: A Sparse Representation Perspective, Zhe Zhang Apr 2012

Vision-Based Human Action Recognition: A Sparse Representation Perspective, Zhe Zhang

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

The objective of vision-based human action recognition is to label the video sequence with its corresponding action category. In this thesis, the human action recognition problem is solved from a novel sparse representation perspective. First, spatial-temporal interest points are extracted in the video sequences. Then, a cuboid is extracted centered at each spatial-temporal interest point. The histogram of oriented gradients (HOG) and histogram of flow (HOF) descriptors for each cuboid are computed and concatenated into a one-dimensional vector. The K-Means clustering algorithm is used to cluster these cuboid feature vectors into a few visual codewords. Finally, each action instance is …


2012 First Annual State Of Resnet Report Jan 2012

2012 First Annual State Of Resnet Report

ACUTA: Other Publications

In This Issue

Introduction

Methodology

Executive Summary

Structure of the ResNet

Network Infrastructure

Staffing, Service & Support

Fees & Budgets


The Acuta Journal Of Information Communications Technology In Higher Education Media Jan 2012

The Acuta Journal Of Information Communications Technology In Higher Education Media

ACUTA: Other Publications

In This Issue

Mission Statement

Editorial Focus

Format

Advertorial

Reader Profile

Our Mission

Who Are ACUTA Members?

Spring 2012

Summer 2012

Fall 2012

Winter 2012

Rate Card 2012

Rate Protection Policy

Payment/Advertising Discounts

Conditions & Guidelines

Mechanical Requirements

Business Reply Cards

Significant Dates

Fractional AD Sizes

Benefits of Corporate Affiliate Membership


Highly Efficient Maximum Power Point Tracking Using A Quasi-Double-Boost Dc/Dc Converter For Photovoltaic Systems, Christopher J. Lohmeier Dec 2011

Highly Efficient Maximum Power Point Tracking Using A Quasi-Double-Boost Dc/Dc Converter For Photovoltaic Systems, Christopher J. Lohmeier

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

Solar photovoltaic (PV) panels are a great source of renewable energy generation. The biggest problem with solar systems is relatively low efficiency and high cost. This work hopes to alleviate this problem by using novel power electronic converter and control designs. An electronic DC/DC converter, called “Quasi-Double-Boost DC/DC Converter,” is designed for a Solar PV system. A Maximum Power Point Tracking (MTTP) algorithm is implemented through this converter. This algorithm allows the PV system to work at its highest efficiency. Different current sensing and sensorless technologies used with the converter for the MPPT algorithm are offered and tested. Design aspects …


Cyclostationary Detection For Ofdm In Cognitive Radio Systems, Marcos E. Castro Aug 2011

Cyclostationary Detection For Ofdm In Cognitive Radio Systems, Marcos E. Castro

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

Research on cognitive radio systems has attracted much interest in the last 10 years. Cognitive radio is born as a paradigm and since then the idea has seen contribution from technical disciplines under different conceptual layers. Since then improvements on processing capabilities have supported the current achievements and even made possible to move some of them from the research arena to markets.

Cognitive radio implies a revolution that is even asking for changes in current business models, changes at the infrastructure levels, changes in legislation and requiring state of the art technology.

Spectrum sensing is maybe the most important part …


Wireless Communications And Cognitive Radio Transmissions Under Quality Of Service Constraints And Channel Uncertainty, Sami Akin May 2011

Wireless Communications And Cognitive Radio Transmissions Under Quality Of Service Constraints And Channel Uncertainty, Sami Akin

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

In this thesis, we study wireless communications and cognitive radio transmissions under quality of service (QoS) constraints and channel uncertainty. Initially, we focus on a time-varying Rayleigh fading channel and assume that no prior channel knowledge is available at the transmitter and the receiver.  We investigate the performance of pilot-assisted wireless transmission strategies. In particular, we analyze different channel estimation techniques, including single-pilot minimum mean-square-error (MMSE) estimation, and causal and noncausal Wiener filters, and analyze efficient resource allocation strategies. Subsequently, we study the training-based transmission and reception schemes over a priori unknown, Rayleigh fading relay channels in which the fading …