Engineering Commons^™

Secure Cloud Controlled Software Defined Radio Network For Bandwidth Allocation, Isaac J. Cushman

Electronic Theses and Dissertations

The purpose of this research is to investigate the impact of mobility of wireless devices for opportunistic spectrum access and communications using National Instrument Universal Software Radio Peripherals devices. The overall system utilizes software defined radio networks for frequency allocation, cloud connectivity to maintain up-to-date information, and moving target defense as a security mechanism. Each USRP device sends its geolocation to query the spectrum database for idle channels. The cloud cluster was designed for complex data storage and allocation using a smart load balancer to offer ultra-security to users. This project also explores the advantages of data protection and security …

Intrusion Detection For Smart Grid Communication Systems, Brycent Chatfield

Electronic Theses and Dissertations

Transformation of the traditional power grid into a smart grid hosts an array of vulnerabilities associated with communication networks. Furthermore, wireless mediums used throughout the smart grid promote an environment where Denial of Service (DoS) attacks are very effective. In wireless mediums, jamming and spoofing attack techniques diminish system operations thus affecting smart grid stability and posing an immediate threat to Confidentiality, Integrity, and Availability (CIA) of the smart grid. Intrusion detection systems (IDS) serve as a primary defense in mitigating network vulnerabilities. In IDS, signatures created from historical data are compared to incoming network traffic to identify abnormalities. In …

Single Carrier Frequency Domain Equalization And Energy Efficiency Optimization For Mimo Cognitive Radio., Xiaohui Zhang

Electronic Theses and Dissertations

This dissertation studies two separate topics in wireless communication systems. One topic focuses on the Single Carrier Frequency Domain Equalization (SC-FDE), which is a promising technique to mitigate the multipath effect in the broadband wireless communication. Another topic targets on the energy efficiency optimization in a multiple input multiple output (MIMO) cognitive radio network. For SC-FDE, the conventional linear receivers suffer from the noise amplification in deep fading channel. To overcome this, a fractional spaced frequency domain (FSFD) receiver based on frequency domain oversampling (FDO) is proposed for SC-FDE to improve the performance of the linear receiver under deep fading …

An Adaptable Fuzzy-Based Model For Predicting Link Quality In Robot Networks., Christopher J. Lowrance

Electronic Theses and Dissertations

It is often essential for robots to maintain wireless connectivity with other systems so that commands, sensor data, and other situational information can be exchanged. Unfortunately, maintaining sufficient connection quality between these systems can be problematic. Robot mobility, combined with the attenuation and rapid dynamics associated with radio wave propagation, can cause frequent link quality (LQ) issues such as degraded throughput, temporary disconnects, or even link failure. In order to proactively mitigate such problems, robots must possess the capability, at the application layer, to gauge the quality of their wireless connections. However, many of the existing approaches lack adaptability or …

Design, Analysis, Implementation And Evaluation Of Real-Time Opportunistic Spectrum Access In Cloud-Based Cognitive Radio Networks, Nimish Sharma

Electronic Theses and Dissertations

Opportunistic spectrum access in cognitive radio network is proposed for remediation of spectrum under-utilization caused by exclusive licensing for service providers that are intermittently utilizing spectrum at any given geolocation and time. The unlicensed secondary users (SUs) rely on opportunistic spectrum access to maximize spectrum utilization by sensing/identifying the idle bands without causing harmful interference to licensed primary users (PUs). In this thesis, Real-time Opportunistic Spectrum Access in Cloud-based Cognitive Radio Networks (ROAR) architecture is presented where cloud computing is used for processing and storage of idle channels. Software-defined radios (SDRs) are used as SUs and PUs that identify, report, …

Heterogeneous Dynamic Spectrum Access In Cognitive Radio Enabled Vehicular Networks Using Network Softwarization, Swetha R. Reddy

Electronic Theses and Dissertations

Dynamic spectrum access (DSA) in cognitive radio networks (CRNs) is regarded as an emerging technology to solve the spectrum scarcity problem created by static spectrum allocation. In DSA, unlicensed users access idle channels opportunistically, without creating any harmful interference to licensed users. This method will also help to incorporate billions of wireless devices for different applications such as Internet-of-Things, cyber-physical systems, smart grids, etc. Vehicular networks for intelligent transportation cyber-physical systems is emerging concept to improve transportation security and reliability. IEEE 802.11p standard comprising of 7 channels is dedicated for vehicular communications. These channels could be highly congested and may …

Design, Analysis And Evaluation Of Unmanned Aerial Vehicle Ad Hoc Network For Emergency Response Communications, Robin D. Grodi

Electronic Theses and Dissertations

In any emergency situation, it is paramount that communication be established between those affected by an emergency and the emergency responders. This communication is typically initiated by contacting an emergency service number such as 9-1-1 which will then notify the appropriate responders. The communication link relies heavily on the use of the public telephone network. If an emergency situation causes damage to, or otherwise interrupts, the public telephone network then those affected by the emergency are unable to call for help or warn others. A backup emergency response communication system is required to restore communication in areas where the public …

Performance Analysis Of Secondary Users In Heterogeneous Cognitive Radio Network, Tanjil Amin

Electronic Theses and Dissertations

Continuous increase in wireless subscriptions and static allocation of wireless frequency bands to the primary users (PUs) are fueling the radio frequency (RF) shortage problem. Cognitive radio network (CRN) is regarded as a solution to this problem as it utilizes the scarce RF in an opportunisticmanner to increase the spectrumefficiency. InCRN, secondary users (SUs) are allowed to access idle frequency bands opportunistically without causing harmful interference to the PUs. In CRN, the SUs determine the presence of PUs through spectrum sensing and access idle bands by means of dynamic spectrum access. Spectrum sensing techniques available in the literature do not …

Ultra-Fast, Autonomous, Reconfigurable Communication System, Paul Bupe Jr

Electronic Theses and Dissertations

The recent years have witnessed an increase in natural disasters in which the destruction of essential communication infrastructure has significantly affected the number of casualties. In 2005, Hurricane Katrina in the United States resulted in over 1,900 deaths, three million land-line phones disconnections, and more than 2000 cell sites going out of service. This incident highlighted an urgent need for a quick-deployment, efficient communication network for emergency relief purposes. In this research, a fully autonomous system to deploy Unmanned Aerial Vehicles (UAVs) as the first phase disaster recovery communication network for wide-area relief is presented. As part of this system, …

Comparing The Efficiency Of Heterogeneous And Homogeneous Data Center Workloads, Brandon Kimmons

Electronic Theses and Dissertations

Abstract

Information Technology, as an industry, is growing very quickly to keep pace with increased data storage and computing needs. Data growth, if not planned or managed correctly, can have larger efficiency implications on your data center as a whole. The long term reduction in efficiency will increase costs over time and increase operational overhead. Similarly, increases in processor efficiency have led to increased system density in data centers. This can increase cost and operational overhead in your data center infrastructure.

This paper proposes the idea that balanced data center workloads are more efficient in comparison to similar levels of …

Design And Analysis Of Circularly Polarized Electrically Small Antennas, Jesse R. Ludwig

Electronic Theses and Dissertations

A growing need for efficient wireless communication is prevalent in the world in which we live. From cell phones to television to GPS applications, wireless communications are vital in consumer electronics and military applications. In these applications, a miniaturized antenna is sometimes necessary for reducing overall size of the communication system. For many satellite based communication applications, circular polarization in antennas is needed for efficient communication. In this thesis, the miniaturization technique known as T-top loading is utilized on two novel antenna designs. One design is an electrically small, circularly polarized planar cross dipole and the other design is a …

Assessment Of Audio Interfaces For Use In Smartphone Based Spatial Learning Systems For The Blind, Shreyans Jain

Electronic Theses and Dissertations

Recent advancements in the field of indoor positioning and mobile computing promise development of smart phone based indoor navigation systems. Currently, the preliminary implementations of such systems only use visual interfaces—meaning that they are inaccessible to blind and low vision users. According to the World Health Organization, about 39 million people in the world are blind. This necessitates the need for development and evaluation of non-visual interfaces for indoor navigation systems that support safe and efficient spatial learning and navigation behavior. This thesis research has empirically evaluated several different approaches through which spatial information about the environment can be conveyed …

Mobile Map Browsers: Anticipated User Interaction For Data Pre-Fetching, Benjamin T. Weber

Electronic Theses and Dissertations

When browsing a graphical display of geospatial data on mobile devices, users typically change the displayed maps by panning, zooming in and out, or rotating the device. Limited storage space on mobile devices and slow wireless communications, however, impede the performance of these operations. To overcome the bottleneck that all map data to be displayed on the mobile device need to be downloaded on demand, this thesis investigates how anticipated user interactions affect intelligent pre-fetching so that an on-demand download session is extended incrementally. User interaction is defined as a set of map operations that each have corresponding effects on …

Architecture For Intelligent Power Systems Management, Optimization, And Storage., J. Chris Foreman

Electronic Theses and Dissertations

The management of power and the optimization of systems generating and using power are critical technologies. A new architecture is developed to advance the current state of the art by providing an intelligent and autonomous solution for power systems management. The architecture is two-layered and implements a decentralized approach by defining software objects, similar to software agents, which provide for local optimization of power devices such as power generating, storage, and load devices. These software device objects also provide an interface to a higher level of optimization. This higher level of optimization implements the second layer in a centralized approach …

Design And Applications Of A Graphics Package For The Hp1000 Computer., Hsiao-Chih George Lee

Electronic Theses and Dissertations

The objective of this thesis is to develop the FORTRAN subroutine PLOTER which is a general-purpose plotting tool to plot charts on a Hewlett Packard plotter. The programs RESP and INVLAP which can plot the frequency and time responses of system functions are modified to adopt the PLOTER subroutine and are stored of the HP1000-A900 minicomputer whose software, the GRAPHICS/1000, supports the graphics ability of PLOTER. This thesis describes the theories, functions, software techniques and operations of the PLOTER subroutine and the application programs RESP and the INVLAP. It also provides program listings and example plots.