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Full-Text Articles in Engineering

Exploitation Of Robust Aoa Estimation And Low Overhead Beamforming In Mmwave Mimo System, Yuyan Zhao Nov 2019

Exploitation Of Robust Aoa Estimation And Low Overhead Beamforming In Mmwave Mimo System, Yuyan Zhao

Electronic Thesis and Dissertation Repository

The limited spectral resource for wireless communications and dramatic proliferation of new applications and services directly necessitate the exploitation of millimeter wave (mmWave) communications. One critical enabling technology for mmWave communications is multi-input multi-output (MIMO), which enables other important physical layer techniques, specifically beamforming and antenna array based angle of arrival (AoA) estimation. Deployment of beamforming and AoA estimation has many challenges. Significant training and feedback overhead is required for beamforming, while conventional AoA estimation methods are not fast or robust. Thus, in this thesis, new algorithms are designed for low overhead beamforming, and robust AoA estimation with significantly reduced ...


Data Analytics And Performance Enhancement In Edge-Cloud Collaborative Internet Of Things Systems, Tianqi Yu Aug 2019

Data Analytics And Performance Enhancement In Edge-Cloud Collaborative Internet Of Things Systems, Tianqi Yu

Electronic Thesis and Dissertation Repository

Based on the evolving communications, computing and embedded systems technologies, Internet of Things (IoT) systems can interconnect not only physical users and devices but also virtual services and objects, which have already been applied to many different application scenarios, such as smart home, smart healthcare, and intelligent transportation. With the rapid development, the number of involving devices increases tremendously. The huge number of devices and correspondingly generated data bring critical challenges to the IoT systems. To enhance the overall performance, this thesis aims to address the related technical issues on IoT data processing and physical topology discovery of the subnets ...


Analysis, Design And Demonstration Of Control Systems Against Insider Attacks In Cyber-Physical Systems, Xirong Ning Jun 2019

Analysis, Design And Demonstration Of Control Systems Against Insider Attacks In Cyber-Physical Systems, Xirong Ning

Electronic Thesis and Dissertation Repository

This dissertation aims to address the security issues of insider cyber-physical attacks and provide a defense-in-depth attack-resilient control system approach for cyber-physical systems.

Firstly, security analysis for cyber-physical systems is investigated to identify potential risks and potential security enhancements. Vulnerabilities of the system and existing security solutions, including attack prevention, attack detection and attack mitigation strategies are analyzed.

Subsequently, a methodology to analyze and mathematically characterize insider attacks is developed. An attack pattern is introduced to represent key features in an insider cyber-physical attack, which includes attack goals, resources, constraints, modes, as well as probable attack paths. Patterns for such ...


Performance Enhancement Of Ieee 802.11ax In Ultra-Dense Wireless Networks, Jiyang Bai Dec 2018

Performance Enhancement Of Ieee 802.11ax In Ultra-Dense Wireless Networks, Jiyang Bai

Electronic Thesis and Dissertation Repository

IEEE 802.11ax, which is one emerging WLAN standard, aims at providing highly efficient communication in ultra-dense wireless networks. However, due to a large number of stations (STAs) in dense deployment scenarios and diverse services to be supported, there are many technical challenges to be overcome. Firstly, the potential high packet collision rate significantly degrades the network efficiency of WLAN. In this thesis, we propose an adaptive station (STA) grouping scheme to overcome this challenge in IEEE 802.11ax using Uplink OFDMA Random Access (UORA). In order to achieve optimal utilization efficiency of resource units (RUs), we first analyze the ...


Current Implementation Of The Flooding Time Synchronization Protocol In Wireless Sensor Networks, Asma Khalil Dec 2018

Current Implementation Of The Flooding Time Synchronization Protocol In Wireless Sensor Networks, Asma Khalil

Electronic Thesis and Dissertation Repository

Time synchronization is an issue that affects data accuracy within wireless sensor networks (WSNs). This issue is due to the complex nature of the wireless medium and can be mitigated with accurate time synchronization. This research focuses on the Flooding Time Synchronization Protocol (FTSP) since it is considered as the gold standard for accuracy in WSNs. FTSP minimizes the synchronization error by executing an algorithm that creates a unified time for the network reporting micro-second accuracy. Most synchronization protocols use the FTSP implementation as a benchmark for comparison. The current and only FTSP implementation runs on the TinyOS platform and ...


Spectral And Energy Efficient Communication Systems And Networks, Abdulbaset Hamed Oct 2018

Spectral And Energy Efficient Communication Systems And Networks, Abdulbaset Hamed

Electronic Thesis and Dissertation Repository

In this thesis, design and analysis of energy- and spectral-efficient communication and cellular systems in micro wave and millimeter wave bands are considered using the following system performance metrics: i) Energy efficiency; ii) Spectral efficiency; iii) Spatial spectral efficiency; iv) Spatial energy efficiency, and v) Bit error rate. Statistical channel distributions, Nakagami-m and Generalized-K, and path loss models, Line of Sight (LOS) and Non-Line of Sight (NLOS), are used to represent the propagation environment in these systems. Adaptive M-QAM and M-CPFSK communication systems are proposed to enhance their efficiency metrics as a function of Signal-to-Noise Ratio (SNR) over the channel ...


Real-Time Intrusion Detection Using Multidimensional Sequence-To-Sequence Machine Learning And Adaptive Stream Processing, Gobinath Loganathan Aug 2018

Real-Time Intrusion Detection Using Multidimensional Sequence-To-Sequence Machine Learning And Adaptive Stream Processing, Gobinath Loganathan

Electronic Thesis and Dissertation Repository

A network intrusion is any unauthorized activity on a computer network. There are host-based and network-based Intrusion Detection Systems (IDS's), of which there are each signature-based and anomaly-based detection methods. An anomalous network behavior can be defined as an intentional violation of the expected sequence of packets. In a real-time network-based IDS, incoming packets are treated as a stream of data. A stream processor takes any stream of data or events and extracts interesting patterns on the fly. This representation allows applying statistical anomaly detection using sequence prediction algorithms as well as using a stream processor to perform signature-based ...


Integration Of Rfid And Industrial Wsns To Create A Smart Industrial Environment, Ning Pan Jul 2018

Integration Of Rfid And Industrial Wsns To Create A Smart Industrial Environment, Ning Pan

Electronic Thesis and Dissertation Repository

A smart environment is a physical space that is seamlessly embedded with sensors, actuators, displays, and computing devices, connected through communication networks for data collection, to enable various pervasive applications. Radio frequency identification (RFID) and Wireless Sensor Networks (WSNs) can be used to create such smart environments, performing sensing, data acquisition, and communication functions, and thus connecting physical devices together to form a smart environment.

This thesis first examines the features and requirements a smart industrial environment. It then focuses on the realization of such an environment by integrating RFID and industrial WSNs. ISA100.11a protocol is considered in particular ...


Constant Envelope Dct- And Fft- Based Multicarrier Systems, Rayan Alsisi Jun 2018

Constant Envelope Dct- And Fft- Based Multicarrier Systems, Rayan Alsisi

Electronic Thesis and Dissertation Repository

Discrete Cosine Transform (DCT)- and Fast Fourier Transform (FFT)- based Orthogonal Frequency Division Multiplexing (OFDM) systems with a variety of angle modulations are considered for data transmission. These modulations are used with the purpose of achieving Constant Envelope (CE) transmitted signals, for superior power efficiency with nonlinear High Power Amplifier (HPA), typically used at the transmitter in OFDM systems. Specifically, four angle modulations are considered: i) Phase Modulation (PM); ii) Frequency Modulation (FM); iii) Continuous Phase Modulation (CPM); and iv) Continuous Phase Chirp Modulation (CPCM). Descriptions of DCT- and FFT- based OFDM systems with M-ary Pulse Amplitude Modulation (MPAM) mapper ...


Design Of An All-Dielectric Sublayer For Enhanced Transmittance In Stacked Antenna Array Applications, Matthew Bester May 2018

Design Of An All-Dielectric Sublayer For Enhanced Transmittance In Stacked Antenna Array Applications, Matthew Bester

Electronic Thesis and Dissertation Repository

In spatially constrained applications, the overlapping of antenna arrays can be unavoidable and its presence can lead to a blockage in the line-of-sight for the underlying antennas. Although previous investigations focused predominantly on the contribution of the ground plane and feed network-which were resolved through the use of frequency selective surfaces and proper feed network design, respectively-it is believed that the ground plane, substrate, and patch regions can emplace a substantial combined impedance. To rectify the transmission through these layers, an all-dielectric implementation is suggested based on the properties of complementary media and Fabry-Perot resonance shifting phenomena. Consequently, both spherical ...


Performance Enhancement By Exploiting The Spatial Domain For Cost, Space And Spectrum Constraint 5g Communication, Golara Zafari Apr 2018

Performance Enhancement By Exploiting The Spatial Domain For Cost, Space And Spectrum Constraint 5g Communication, Golara Zafari

Electronic Thesis and Dissertation Repository

With everlasting increase of connectivity demand and high speed data communication, lots of progresses have been made to provide a sufficient quality of services (QoS). Several advanced technologies have been the cornerstone of this trend in academia as well as in industry. Nevertheless, there are some implementation challenges, which needs to be closely investigated. In this thesis, among all challenges, we elaborate on those related to number of radio frequency (RF) chains and resource scarcity.

The principle idea behind our proposed initial solution is to exploit the spatial domain as an additional degree of freedom. To be more specific, we ...


Efficient Traffic Management Algorithms For The Core Network Using Device-To-Device Communication And Edge Caching, Hessam Yousefi Apr 2018

Efficient Traffic Management Algorithms For The Core Network Using Device-To-Device Communication And Edge Caching, Hessam Yousefi

Electronic Thesis and Dissertation Repository

Exponentially growing number of communicating devices and the need for faster, more reliable and secure communication are becoming major challenges for current mobile communication architecture. More number of connected devices means more bandwidth and a need for higher Quality of Service (QoS) requirements, which bring new challenges in terms of resource and traffic management. Traffic offload to the edge has been introduced to tackle this demand-explosion that let the core network offload some of the contents to the edge to reduce the traffic congestion. Device-to-Device (D2D) communication and edge caching, has been proposed as promising solutions for offloading data. D2D ...


Intelligent Advancements In Location Management And C-Ran Power-Aware Resource Allocation, Emad Ali Aqeeli Dec 2017

Intelligent Advancements In Location Management And C-Ran Power-Aware Resource Allocation, Emad Ali Aqeeli

Electronic Thesis and Dissertation Repository

The evolving of cellular networks within the last decade continues to focus on delivering a robust and reliable means to cope with the increasing number of users and demanded capacity. Recent advancements of cellular networks such as Long-Term Evolution (LTE) and LTE-advanced offer a remarkable high bandwidth connectivity delivered to the users. Signalling overhead is one of the vital issues that impact the cellular behavior. Causing a significant load in the core network hence effecting the cellular network reliability. Moreover, the signaling overhead decreases the Quality of Experience (QoE) of users. The first topic of the thesis attempts to reduce ...


Efficiency And Accuracy Enhancement Of Intrusion Detection System Using Feature Selection And Cross-Layer Mechanism, Mahsa Bataghva Nov 2017

Efficiency And Accuracy Enhancement Of Intrusion Detection System Using Feature Selection And Cross-Layer Mechanism, Mahsa Bataghva

Electronic Thesis and Dissertation Repository

The dramatic increase in the number of connected devices and the significant growth of the network traffic data have led to many security vulnerabilities and cyber-attacks. Hence, developing new methods to secure the network infrastructure and protect data from malicious and unauthorized access becomes a vital aspect of communication network design. Intrusion Detection Systems (IDSs), as common widely used security techniques, are critical to detect network attacks and unauthorized network access and thus minimize further cyber-attack damages. However, there are a number of weaknesses that need to be addressed to make reliable IDS for real-world applications. One of the fundamental ...


Software-Defined Networking Enabled Resource Management And Security Provisioning In 5g Heterogeneous Networks, Xiaoyu Duan Jul 2017

Software-Defined Networking Enabled Resource Management And Security Provisioning In 5g Heterogeneous Networks, Xiaoyu Duan

Electronic Thesis and Dissertation Repository

Due to the explosive growth of mobile data traffic and the shortage of spectral resources, 5G networks are envisioned to have a densified heterogeneous network (HetNet) architecture, combining multiple radio access technologies (multi-RATs) into a single holistic network. The co-existing of multi-tier architectures bring new challenges, especially on resource management and security provisioning, due to the lack of common interface and consistent policy across HetNets. In this thesis, we aim to address the technical challenges of data traffic management, coordinated spectrum sharing and security provisioning in 5G HetNets through the introduction of a programmable management platform based on Software-defined networking ...


Efficient Macromodeling And Fast Transient Simulation Of High Speed Distributed Interconnects, Sadia Wahid Jun 2017

Efficient Macromodeling And Fast Transient Simulation Of High Speed Distributed Interconnects, Sadia Wahid

Electronic Thesis and Dissertation Repository

In the first part of the thesis, an efficient macromodeling technique based on Loewner Matrix (LM) approach has been presented to model multi-port distributed systems using tabulated noisy data. In the proposed method, Loewner Model data from previous rational approximation are used to create less noisy eigenvectors in an iterative manner. As a result, the biasing effect of the LM model approximated by the noisy data is reduced. It is illustrated that this method improves the accuracy of the Loewner Matrix modeling for noisy frequency data.

In the second part, a fast and robust algorithm is introduced for time-domain simulation ...


Modelling And Analysis Of Smart Grids For Critical Data Communication, Abdulfattah Noorwali Dec 2016

Modelling And Analysis Of Smart Grids For Critical Data Communication, Abdulfattah Noorwali

Electronic Thesis and Dissertation Repository

Practical models for the subnetworks of smart grid are presented and analyzed. Critical packet-delay bounds for these subnetworks are determined, with the overall objective of identifying parameters that would help in the design of smart grid with least end-to-end delay.

A single-server non-preemptive queueing model with prioritized critical packets is presented for Home Area Network (HAN). Closed-form expressions for critical packet delay are derived and illustrated as a function of: i) critical packet arrival rate, ii) service rate, iii) utilization factor, and iv) rate of arrival of non-critical packets. Next, wireless HANs using FDMA and TDMA are presented. Upper and ...


Improved Localization Algorithms In Indoor Wireless Environment, Fei Long Nov 2016

Improved Localization Algorithms In Indoor Wireless Environment, Fei Long

Electronic Thesis and Dissertation Repository

Localization has been considered as an important precondition for the location-dependent applications such as mobile tracking and navigation.To obtain specific location information, we usually make use of Global Positioning System(GPS), which is the most common plat- form to acquire localization information in outdoor environments. When targets are in indoor environment, however, the GPS signal is usually blocked, so we also consider other assisted positioning techniques in order to obtain accurate position of targets. In this thesis, three different schemes in indoor environment are proposed to minimize localization error by placing refer- ence nodes in optimum locations, combining the ...


Radio Resource Management Optimization For Next Generation Wireless Networks, Karim Ahmed Hammad Nov 2016

Radio Resource Management Optimization For Next Generation Wireless Networks, Karim Ahmed Hammad

Electronic Thesis and Dissertation Repository

The prominent versatility of today’s mobile broadband services and the rapid advancements in the cellular phones industry have led to a tremendous expansion in the wireless market volume. Despite the continuous progress in the radio-access technologies to cope with that expansion, many challenges still remain that need to be addressed by both the research and industrial sectors. One of the many remaining challenges is the efficient allocation and management of wireless network resources when using the latest cellular radio technologies (e.g., 4G). The importance of the problem stems from the scarcity of the wireless spectral resources, the large ...


Efficient Macromodeling Techniques Of Distributed Networks Using Tabulated Data, Mohamed Sahouli Oct 2016

Efficient Macromodeling Techniques Of Distributed Networks Using Tabulated Data, Mohamed Sahouli

Electronic Thesis and Dissertation Repository

Efficient macromodeling techniques used to model multi-port distributed systems using tabulated data are presented. First a method to macromodel large multiport systems characterized by noisy frequency domain data is shown. The proposed method is based on the vector fitting algorithm and uses an instrumental variable approach and QR decomposition to formulate the least squares equations. The instrumental variable method minimizes the biasing effect of the least squares solution caused by the noise of the data samples while QR decomposition decouples the least squares equations of multiport systems described by common set of poles. It is illustrated, that the proposed approach ...


Controlling And Processing Core For Wireless Implantable Telemetry System, Naeeme Modir Oct 2016

Controlling And Processing Core For Wireless Implantable Telemetry System, Naeeme Modir

Electronic Thesis and Dissertation Repository

Wireless implantable telemetry systems are suitable choices for monitoring various physiological parameters such as blood pressure and volume. These systems typically compose of an internal device implanted into a living body captures the physiological data and sends them to an external base station located outside of the body for further processing. The internal device usually consists of a sensor interface to convert the collected data to electrical signals; a digital core to digitize the analog signals, process them and prepare them for transmission; an RF front-end to transmit the data outside the body and to receive the required commands from ...


Efficient And Virtualized Scheduling For Ofdm-Based High Mobility Wireless Communications Objects, Mohamed Hussein Abdelwahab Ahmed Aug 2016

Efficient And Virtualized Scheduling For Ofdm-Based High Mobility Wireless Communications Objects, Mohamed Hussein Abdelwahab Ahmed

Electronic Thesis and Dissertation Repository

Services providers (SPs) in the radio platform technology standard long term evolution (LTE) systems are enduring many challenges in order to accommodate the rapid expansion of mobile data usage. The modern technologies demonstrate new challenges to SPs, for example, reducing the cost of the capital and operating expenditures while supporting high data throughput per customer, extending battery life-per-charge of the cell phone devices, and supporting high mobility communications with fast and seamless handover (HO) networking architecture. In this thesis, a variety of optimized techniques aimed at providing innovative solutions for such challenges are explored. The thesis is divided into three ...


Spectrally Efficient Cooperative Relay Networks Using Signal Space Diversity, Muhammad Ajmal Khan Jun 2016

Spectrally Efficient Cooperative Relay Networks Using Signal Space Diversity, Muhammad Ajmal Khan

Electronic Thesis and Dissertation Repository

Cooperative relaying has received widespread attention in recent years from both academic and industrial communities. It offers significant benefits in enabling connectivity as well as in increasing coverage, power saving, spatial diversity and channel capacity. However, one of the main limitations of the conventional cooperative relaying system is the repetition of the received data by the relays, which reduces the spectral efficiency and the data rate. In this thesis, signal space diversity (SSD) based technique is proposed to incorporate into the conventional relaying system to enhance spectral efficiency, data rate and system performance.

Firstly, SSD is introduced into a two-way ...


Constant-Envelope Multi-Level Chirp Modulation: Properties, Receivers, And Performance, Mohammad A. Alsharef Feb 2016

Constant-Envelope Multi-Level Chirp Modulation: Properties, Receivers, And Performance, Mohammad A. Alsharef

Electronic Thesis and Dissertation Repository

Constant envelope multi-level chirp modulations, with and without memory, are considered for data transmission. Specifically, three sub-classes referred to as symbol-by-symbol multi-level chirp modulation, full-response phase-continuous multi-level chirp modulation and full-response multi-mode phase-continuous multi-level chirp modulation are considered. These modulated signals are described, illustrated, and examined for their properties. The ability of these signals to operate over AWGN is assessed using upper bounds on minimum Euclidean distance as a function of modulation parameters. Coherent and non-coherent detection of multi-level chirp signals in AWGN are considered and optimum and sub-optimum receiver structures are derived. The performance of these receivers have been ...


Wireless Device Authentication Techniques Using Physical-Layer Device Fingerprint, Peng Hao Nov 2015

Wireless Device Authentication Techniques Using Physical-Layer Device Fingerprint, Peng Hao

Electronic Thesis and Dissertation Repository

Due to the open nature of the radio signal propagation medium, wireless communication is inherently more vulnerable to various attacks than wired communication. Consequently, communication security is always one of the critical concerns in wireless networks. Given that the sophisticated adversaries may cover up their malicious behaviors through impersonation of legitimate devices, reliable wireless authentication is becoming indispensable to prevent such impersonation-based attacks through verification of the claimed identities of wireless devices.

Conventional wireless authentication is achieved above the physical layer using upper-layer identities and key-based cryptography. As a result, user authenticity can even be validated for the malicious attackers ...


Secrecy Enhancement In Cooperative Relaying Systems, Elham Nosrati Oct 2015

Secrecy Enhancement In Cooperative Relaying Systems, Elham Nosrati

Electronic Thesis and Dissertation Repository

Cooperative communications is obviously an evolution in wireless networks due to its noticeable advantages such as increasing the coverage as well as combating fading and shadowing effects. However, the broadcast characteristic of a wireless medium which is exploited in cooperative communications leads to a variety of security vulnerabilities. As cooperative communication networks are globally expanded, they expose to security attacks and threats more than ever. Primarily, researchers have focused on upper layers of network architectures to meet the requirements for secure cooperative transmission while the upper-layer security solutions are incapable of combating a number of security threats, e.g., jamming ...


On Enhancements Of Physical Layer Secret Key Generation And Its Application In Wireless Communication Systems, Kang Liu Oct 2015

On Enhancements Of Physical Layer Secret Key Generation And Its Application In Wireless Communication Systems, Kang Liu

Electronic Thesis and Dissertation Repository

As an alternative and appealing approach to providing information security in wireless communication systems, secret key generation at physical layer has demonstrated its potential in terms of efficiency and reliability over traditional cryptographic methods. Without the necessity of a management centre for key distribution or reliance on computational complexity, physical layer key generation protocols enable two wireless entities to extract identical and dynamic keys from the randomness of the wireless channels associated with them.

In this thesis, the reliability of secret key generation at the physical layer is examined in practical wireless channels with imperfect channel state information (CSI). Theoretical ...


Analysis And Compensation Of Power Amplifier Distortions In Wireless Communication Systems, Sharath Manjunath Oct 2015

Analysis And Compensation Of Power Amplifier Distortions In Wireless Communication Systems, Sharath Manjunath

Electronic Thesis and Dissertation Repository

Wireless communication devices transmit message signals which should possess desirable power levels for quality transmission. Power amplifiers are devices in the wireless transmitters which increase the power of signals to the desired levels, but produce nonlinear distortions due to their saturation property, resulting in degradation of the quality of the transmitted signal. This thesis talks about the analysis and performance of communication systems in presence of power amplifier nonlinear distortions.

First, the thesis studies the effects of power amplifier nonlinear distortions on communication signals and proposes a simplified design for identification and compensation of the distortions at the receiver end ...


Endoscopic Targeting Tasks Simulator: An Approach Using Game Engines, Shaun W. Carnegie Sep 2015

Endoscopic Targeting Tasks Simulator: An Approach Using Game Engines, Shaun W. Carnegie

Electronic Thesis and Dissertation Repository

The pervasiveness of simulators used in professions requiring the skilled control of expensive machinery such as is the case in the aviation, mining, construction, and naval industries raises an intriguing question about the relatively poor adoption within the field of medicine. Certain surgical procedures such as neuro-endoscopic and laparoscopic lend themselves well to the application of virtual reality based simulators. This is due to the innate ability to decom- pose these complex macro level procedures into a hierarchy of subtasks that can be modelled in a software simulator to augment existing teaching and training techniques.

The research in this thesis ...


Elastic Highly Available Cloud Computing, Hassan Hawilo Aug 2015

Elastic Highly Available Cloud Computing, Hassan Hawilo

Electronic Thesis and Dissertation Repository

High availability and elasticity are two the cloud computing services technical features. Elasticity is a key feature of cloud computing where provisioning of resources is closely tied to the runtime demand. High availability assure that cloud applications are resilient to failures. Existing cloud solutions focus on providing both features at the level of the virtual resource through virtual machines by managing their restart, addition, and removal as needed. These existing solutions map applications to a specific design, which is not suitable for many applications especially virtualized telecommunication applications that are required to meet carrier grade standards. Carrier grade applications typically ...