UNT Theses and Dissertations - 148 Matching Results

Search Results

prev Results: 41 - 64 next
open access

Design of a Wideband Class J Power Amplifier

Description: A conventional RF power amplifier will convert the low powered radio frequency signals into high powered signals. Along with the expected ability to increase the communication distance, data transfer rates, RF power amplifiers also have many applications which include military radar system, whether forecasting, etc. The main objective of any power amplifier research is to increase the efficiency while maintaining linearity and broadening the frequency of operation. The main motivation for the r… more
Date: May 2013
Creator: Raavi, Srinivasa
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Design of Frequency Output Pressure Transducer

Description: Piezoelectricity crystal is used in different area in industry, such as downhole oil, gas industry, and ballistics. The piezoelectricity crystals are able to create electric fields due to mechanical deformation called the direct piezoelectric effect, or create mechanical deformation due to the effect of electric field called the indirect piezoelectric effect. In this thesis, piezoelectricity effect is the core part. There are 4 parts in the frequency output pressure transducer: two crystal osci… more
Date: August 2015
Creator: Ma, Jinge
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Design of Low-Power Front End Compressive Sensing Circuitry and Energy Harvesting Transducer Modeling for Self-Powered Motion Sensor

Description: Compressed sensing (CS) is an innovative approach of signal processing that facilitates sub-Nyquist processing of bio-signals, such as a neural signal, electrocardiogram (ECG), and electroencephalogram (EEG). This strategy can be used to lower the data rate to realize ultra-low-power performance, As the count of recording channels increases, data volume is increased resulting in impermissible transmitting power. This thesis work presents the implementation of a CMOS-based front-end design with … more
Date: August 2021
Creator: Kakaraparty, Karthikeya Anil Kumar
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Design of Multi Band Microwave Devices Using Coupled Line Transmission Lines

Description: Multi band technology helps in getting multiple operating frequencies using a single microwave device. This thesis presents the design of dual and tri band microwave devices using coupled transmission line structures. Chapter 2 presents the design of a novel dual band transmission line structure using coupled lines. In chapter 3, Design of a dual band branch line coupler and a dual band Wilkinson power divider are proposed using the novel dual band transmission line structure presented in the p… more
Date: May 2015
Creator: Katakam, Sri
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Design of Tunable/Reconfigurable and Compact Microwave Devices

Description: With the rapid development of the modern technology, radio frequency and microwave systems are playing more and more important roles. Since the time the first microwave device was invented, they have been leading not only the military but also our daily life to a new era. In order to make the devices have more practical applications, more and more strict requirements have been imposed. For example, good adaptability, reduced cost and shrank size are highly required. In this thesis, three devic… more
Date: May 2014
Creator: Zhou, Mi
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Design of Ultra Wideband Low Noise Amplifier for Satellite Communications

Description: This thesis offers the design and improvement of a 2 GHz to 20 GHz low noise amplifier (LNA) utilizing pHEMT technology. The pHEMT technology allows the LNA to generate a boosted signal at a lower noise figure (NF) while consuming less power and achieving smooth overall gain. The design achieves an overall gain (S21) of ≥ 10 dB with an NF ≤ 2 dB while consuming ≤ 30 mA of power while using commercial off-the-shelf (COTS) components.
Date: May 2020
Creator: Webber, Scott
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Design of Voltage Boosting Rectifiers for Wireless Power Transfer Systems

Description: This thesis presents a multi-stage rectifier for wireless power transfer in biomedical implant systems. The rectifier is built using Schottky diodes. The design has been simulated in 0.5µm and 130nm CMOS processes. The challenges for a rectifier in a wireless power transfer systems are observed to be the efficiency, output voltage yield, operating frequency range and the minimum input voltage the rectifier can convert. The rectifier outperformed the contemporary works in the mentioned criteria.
Date: May 2019
Creator: Suri, Ramaa Saket
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Design Space Exploration of Domain Specific CGRAs Using Crowd-sourcing

Description: CGRAs (coarse grained reconfigurable array architectures) try to fill the gap between FPGAs and ASICs. Over three decades, the research towards CGRA design has produced number of architectures. Each of these designs lie at different points on a line drawn between FPGAs and ASICs, depending on the tradeoffs and design choices made during the design of architectures. Thus, design space exploration (DSE) takes a very important role in the circuit design process. In this work I propose the design spa… more
Date: August 2014
Creator: Sistla, Anil Kumar
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Development and Analysis of a Mobile Node Tracking Antenna Control System

Description: A wireless communication system allows two parties to exchange information over long distances. The antenna is the component of a wireless communication system that allows information to be converted into electromagnetic radiation that propagates through the air. A system using an antenna with a highly directional beam pattern allows for high power transmission and reception of data. For a directional antenna to serve its purpose, it must be accurately pointed at the object it is communicating … more
Date: August 2017
Creator: Hensley, Phillip Hayden
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Development and Application of Novel Computer Vision and Machine Learning Techniques

Description: The following thesis proposes solutions to problems in two main areas of focus, computer vision and machine learning. Chapter 2 utilizes traditional computer vision methods implemented in a novel manner to successfully identify overlays contained in broadcast footage. The remaining chapters explore machine learning algorithms and apply them in various manners to big data, multi-channel image data, and ECG data. L1 and L2 principal component analysis (PCA) algorithms are implemented and tested a… more
Date: August 2021
Creator: Depoian, Arthur Charles, II
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Development and Integration of a Low-Cost Occupancy Monitoring System

Description: The world is getting busier and more crowded each year. Due to this fact resources such as public transport, available energy, and usable space are becoming congested and require vast amounts of logistical support. As of February 2018, nearly 95% of Americans own a mobile cell phone according to the Pew Research Center. These devices are consistently broadcasting their presents to other devices. By leveraging this data to provide occupational awareness of high traffic areas such as public tran… more
Date: December 2018
Creator: Mahjoub, Youssif
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Development Of A Testbed For Multimedia Environmental Monitoring

Description: Multimedia environmental monitoring involves capturing valuable visual and audio information from the field station. This will permit the environmentalists and researchers to analyze the habitat and vegetation of a region with respect to other environmental specifics like temperature, soil moisture, etc. This thesis deals with the development of a test bed for multimedia monitoring by capturing image information and making it available for the public. A USB camera and a Single board computer ar… more
Date: December 2011
Creator: Kandula, Harsha
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Development of a Wireless Sensor Network System for Occupancy Monitoring

Description: The ways that people use libraries have changed drastically over the past few decades. Proliferation of computers and the internet have led to the purpose of libraries expanding from being only places where information is stored, to spaces where people teach, learn, create, and collaborate. Due to this, the ways that people occupy the space in a library have also changed. To keep up with these changes and improve patron experience, institutions collect data to determine how their spaces are bei… more
Date: December 2018
Creator: Onoriose, Ovie
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Development of High Gain Ultraviolet Photo Detectors Based on Zinc Oxide Nanowires

Description: Semiconductor nanowires acts as an emerging class of materials with great potential for applications in future electronic devices. Small size, large surface to volume ratio and high carrier mobility of nanowires make them potentially useful for electronic applications with high integration density. In this thesis, the focus was on the growth of high quality ZnO nanowires, fabrication of field effect transistors and UV- photodetectros based on them. Intrinsic nanowire parameters such as carrier … more
Date: May 2014
Creator: Mallampati, Bhargav
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Development of Indium Oxide Nanowires as Efficient Gas Sensors

Description: Crystalline indium oxide nanowires were synthesized following optimization of growth parameters. Oxygen vacancies were found to impact the optical and electronic properties of the as-grown nanowires. Photoluminescence measurements showed a strong U.V emission peak at 3.18 eV and defect peaks in the visible region at 2.85 eV, 2.66 eV and 2.5 eV. The defect peaks are attributed to neutral and charged states of oxygen vacancies. Post-growth annealing in oxygen environment and passivation with sulp… more
Date: December 2011
Creator: Gali, Pradeep
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Development of Silicon Nanowire Field Effect Transistors

Description: An economically reliable technique for the synthesis of silicon nanowire was developed using silicon chloride as source material. The 30-40 micron long nanowires were found to have diameters ranging from 40 – 100 nm. An amorphous oxide shell covered the nanowires, post-growth. Raman spectroscopy confirmed the composition of the shell to be silicon-dioxide. Photoluminescence measurements of the as-grown nanowires showed green emission, attributed to the presence of the oxide shell. Etching of th… more
Date: December 2011
Creator: Nukala, Prathyusha
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Development of Wireless Sensor Network System for Indoor Air Quality Monitoring

Description: This thesis describes development of low cost indoor air quality (IAQ) monitoring system for research. It describes data collection of various parameters concentration present in indoor air and sends data back to host PC for further processing. Thesis gives detailed information about hardware and software implementation of IAQ monitoring system. Also discussed are building wireless ZigBee network, creating user friendly graphical user interface (GUI) and analysis of obtained results in comparis… more
Date: December 2012
Creator: Borkar, Chirag
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Distributed Consensus, Optimization and Computation in Networked Systems

Description: In the first part of this thesis, we propose a distributed consensus algorithm under multi-layer multi-group structure with communication time delays. It is proven that the consensus will be achieved in both time-varying and fixed communication delays. In the second part, we study the distributed optimization problem with a finite-time mechanism. It is shown that our distributed proportional-integral algorithm can exponentially converge to the unique global minimizer when the gain parameters sa… more
Date: December 2018
Creator: Yao, Lisha
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Distributed Source Coding with LDPC Codes: Algorithms and Applications

Description: The syndrome source coding for lossless data compression with side information based on fixed-length linear block codes is the main emphasis of this work. We demonstrate that the source entropy rate can be achieved for syndrome source coding with side information when the sources are correlated. Next, we examine employing LDPC codes to apply the channel and syndrome concepts in order to satisfy the Slepian Wolf limit. Our findings indicate that irregular codes perform significantly better when … more
Date: December 2022
Creator: Gandhi, Himani Chirag
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Dual-band Microwave Components And Their Applications

Description: In general, Dual-Band technology enables microwave components to work at two different frequencies. This thesis introduces novel dual-band microwave components and their applications. Chapter 2 presents a novel compact dual-band balun (converting unbalanced signals to balanced ones). The ratio between two working frequencies is analyzed. A novel compact microstrip crossover (letting two lines to cross each other with very high isolation) and its dual-band application is the subject of chapter 3… more
Date: December 2011
Creator: Shao, Jin
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Dual-band Microwave Device Design

Description: This thesis presents a brief introduction to microwave components and technology. It also presents two novel dual-band designs, their analysis, topology, simulation and fabrication. In chapter 2, a novel dual-band bandpass filter using asymmetric stub-loaded stepped-impedance resonators (SLSIRs) operating at 1 and 2.6 GHz is shown. This type of design applies suitable arrangements to improve the filter’s performance. Then, in chapter 3, a novel dual-band balun (transforms unbalanced input sign… more
Date: May 2014
Creator: Li Shen, Andres E.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Dual-Band Quarter Wavelength and Half Wavelength Microstrip Transmission Line Design

Description: The thesis represents the design for dual-band quarter wavelength and half wavelength microstrip transmission line. Chapter 2 proposed the design of a novel dual-band asymmetric pi-shaped short-circuited quarter wavelength microstrip transmission line working at frequencies 1GHz and 1.55 GHz for 50Ω transmission line and at frequencies 1GHz and 1.43GHz for 60Ω transmission line. Chapter 3 proposed the design of a novel dual-band quarter wavelength microstrip transmission line with asymmetricall… more
Date: May 2015
Creator: Imran, Md Asheque
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Dynamic WIFI Fingerprinting Indoor Positioning System

Description: A technique is proposed to improve the accuracy of indoor positioning systems based on WIFI radio-frequency signals by using dynamic access points and fingerprints (DAFs). Moreover, an indoor position system that relies solely in DAFs is proposed. The walking pattern of indoor users is classified as dynamic or static for indoor positioning purposes. I demonstrate that the performance of a conventional indoor positioning system that uses static fingerprints can be enhanced by considering dynamic… more
Date: August 2014
Creator: Reyes, Omar Costilla
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

EEG Signal Analysis in Decision Making

Description: Decision making can be a complicated process involving perception of the present situation, past experience and knowledge necessary to foresee a better future. This cognitive process is one of the essential human ability that is required from everyday walk of life to making major life choices. Although it may seem ambiguous to translate such a primitive process into quantifiable science, the goal of this thesis is to break it down to signal processing and quantifying the thought process with pr… more
Date: May 2017
Creator: Salma, Nabila
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
Back to Top of Screen