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Comparative Study of RSS-Based Collaborative Localization Methods in Wireless Sensor Networks

Description: In this thesis two collaborative localization techniques are studied: multidimensional scaling (MDS) and maximum likelihood estimator (MLE). A synthesis of a new location estimation method through a serial integration of these two techniques, such that an estimate is first obtained using MDS and then MLE is employed to fine-tune the MDS solution, was the subject of this research using various simulation and experimental studies. In the simulations, important issues including the effects of sens… more
Date: December 2006
Creator: Koneru, Avanthi
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Grid-based Coordinated Routing in Wireless Sensor Networks

Description: Wireless sensor networks are battery-powered ad-hoc networks in which sensor nodes that are scattered over a region connect to each other and form multi-hop networks. These nodes are equipped with sensors such as temperature sensors, pressure sensors, and light sensors and can be queried to get the corresponding values for analysis. However, since they are battery operated, care has to be taken so that these nodes use energy efficiently. One of the areas in sensor networks where an energy analy… more
Date: December 2006
Creator: Sawant, Uttara
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Comparison of Source Diversity and Channel Diversity Methods on Symmetric and Fading Channels.

Description: Channel diversity techniques are effective ways to combat channel fading and noise in communication systems. In this thesis, I compare the performance of source and channel diversity techniques on fading and symmetric continuous channels. My experiments suggest that when SNR is low, channel diversity performs better, and when SNR is high, source diversity shows better performance than channel diversity.
Date: August 2009
Creator: Li, Li
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Integrating environmental data acquisition and low cost Wi-Fi data communication.

Description: This thesis describes environmental data collection and transmission from the field to a server using Wi-Fi. Also discussed are components, radio wave propagation, received power calculations, and throughput tests. Measured receive power resulted close to calculated and simulated values. Throughput tests resulted satisfactory. The thesis provides detailed systematic procedures for Wi-Fi radio link setup and techniques to optimize the quality of a radio link.
Date: December 2009
Creator: Gurung, Sanjaya
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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A New Wireless Sensor Node Design for Program Isolation and Power Flexibility

Description: Over-the-air programming systems for wireless sensor networks have drawbacks that stem from fundamental limitations in the hardware used in current sensor nodes. Also, advances in technology make it feasible to use capacitors as the sole energy storage mechanism for sensor nodes using energy harvesting, but most current designs require additional electronics. These two considerations led to the design of a new sensor node. A microcontroller was chosen that meets the Popek and Goldberg virtualiz… more
Date: December 2009
Creator: Skelton, Adam W.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Flight Control Subsystem

Description: Paper describes a project with the goal of designing and prototyping a small-scale unmanned aerial vehicle (UAV), offering dual-channel real-time video, data logging, and waypoint tracking.
Date: 2010
Creator: Williams, Jennifer; Bratton, David; Jones, Aaron; Anderson, Alyse; Befort, Jonathan; Lowe, Ryan et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries
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Design and Implementation of Large-Scale Wireless Sensor Networks for Environmental Monitoring Applications

Description: Environmental monitoring represents a major application domain for wireless sensor networks (WSN). However, despite significant advances in recent years, there are still many challenging issues to be addressed to exploit the full potential of the emerging WSN technology. In this dissertation, we introduce the design and implementation of low-power wireless sensor networks for long-term, autonomous, and near-real-time environmental monitoring applications. We have developed an out-of-box solutio… more
Date: May 2010
Creator: Yang, Jue
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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A Study of Anti-collision Multi-tag Identification Algorithms for Passive RFID Systems

Description: The major advantages of radio frequency identification (RFID) technology over barcodes are that the RFID-tagged objects do not require to be in line-of-sight with the reader for their identification and multiple objects can be read simultaneously. But when multiple objects are read simultaneously there is always a problem of collision which reduces the efficiency of the system. This thesis presents a comprehensive study of the dynamic framed slotted ALOHA (DFSA)-based anti-collision multi-tag i… more
Date: May 2010
Creator: Kamineni, Neelima
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Electronic Sound Analysis with Hardware System and Remote Internet Display

Description: Currently, standards from government agencies such as the National Institute for Occupation Safety and Health exist to aid in safeguarding individuals’ capacity for hearing, but only in factory settings in which large machines often produce loud levels of sound. Neglecting the fact that these preventative measures are only in place in the most limited of settings, no system currently exists to observe and report sound exposure levels in a manner timely or easily recognizable enough to adequatel… more
Date: August 2010
Creator: McCord, Cameron Forrest
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Consensus Building in Sensor Networks and Long Term Planning for the National Airspace System

Description: In this thesis, I present my study on the impact of multi-group network structure on the performance of consensus building strategies, and the preliminary mathematical formulation of the problem on improving the performance of the National Airspace system (NAS) through long-term investment. The first part of the thesis is concerned with a structural approach to the consensus building problem in multi-group distributed sensor networks (DSNs) that can be represented by bipartite graph. Direct i… more
Date: May 2011
Creator: Akula, Naga Venkata Swathik
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Physical-Layer Network Coding for MIMO Systems

Description: The future wireless communication systems are required to meet the growing demands of reliability, bandwidth capacity, and mobility. However, as corruptions such as fading effects, thermal noise, are present in the channel, the occurrence of errors is unavoidable. Motivated by this, the work in this dissertation attempts to improve the system performance by way of exploiting schemes which statistically reduce the error rate, and in turn boost the system throughput. The network can be studied us… more
Date: May 2011
Creator: Xu, Ning
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Toward a Data-Type-Based Real Time Geospatial Data Stream Management System

Description: The advent of sensory and communication technologies enables the generation and consumption of large volumes of streaming data. Many of these data streams are geo-referenced. Existing spatio-temporal databases and data stream management systems are not capable of handling real time queries on spatial extents. In this thesis, we investigated several fundamental research issues toward building a data-type-based real time geospatial data stream management system. The thesis makes contributions in … more
Date: May 2011
Creator: Zhang, Chengyang
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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A Bidirectional Two-Hop Relay Network Using GNU Radio and USRP

Description: A bidirectional two-hop relay network with decode-and-forward strategy is implemented using GNU Radio (software) and several USRPs (hardware) on Ubuntu (operating system). The relay communication system is comprised of three nodes; Base Station A, Base Station B, and Relay Station (the intermediate node). During the first time slot, Base Station A and Base Station B will each transmit data, e.g., a JPEG file, to Relay Station using DBPSK modulation and FDMA. For the final time slot, Relay Stati… more
Date: August 2011
Creator: Le, Johnny
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Design and Implementation of Broad Band and Narrow Band Antennas and Their Applications

Description: The thesis deals with the design and implementation of broadband and narrowband antennas and their applications in practical environment. In this thesis, a new concept for designing the UWB antenna is proposed based on the CRLH metamaterials and this UWB antenna covers a frequency range from 2.45 GHz to 11.6 GHz. Based on the design of the UWB antenna, another antenna is developed that can cover a very wide bandwidth i.e from 0.66 GHz to 120 GHz. This antenna can not only be used for UWB applic… more
Date: August 2011
Creator: Salmani, Zeeshan
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

A Real-Time Electronic Sound Analysis System with Graphical User Interface

Description: Noise-induced hearing loss is a serious problem common to musical environments. Current dosimetry technology is primarily designed for industrial environments and not suited for musical settings. At present, there are no government regulations that apply to the educational music environment as it relates to monitoring and prevention of hearing loss. Also, no system exists than can serve as a proactive tool in observation and reporting of sound exposure levels with the goal of hearing conservati… more
Date: August 2011
Creator: Brgulja, Amir
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Scene Analysis Using Scale Invariant Feature Extraction and Probabilistic Modeling

Description: Conventional pattern recognition systems have two components: feature analysis and pattern classification. For any object in an image, features could be considered as the major characteristic of the object either for object recognition or object tracking purpose. Features extracted from a training image, can be used to identify the object when attempting to locate the object in a test image containing many other objects. To perform reliable scene analysis, it is important that the features extr… more
Date: August 2011
Creator: Shen, Yao
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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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

Data Compression Using a Multi-residue System (Mrs)

Description: This work presents a novel technique for data compression based on multi-residue number systems. The basic theorem is that an under-determined system of congruences could be solved to accomplish data compression for a signal satisfying continuity of its information content and bounded in peak-to -peak amplitude by the product of relatively prime moduli,. This thesis investigates this property and presents quantitative results along with MATLAB codes. Chapter 1 is introductory in nature and Chap… more
Date: August 2012
Creator: Melaedavattil Jaganathan, Jyothy
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Characterization of Ecg Signal Using Programmable System on Chip

Description: Electrocardiography (ECG) monitor is a medical device for recording the electrical activities of the heart using electrodes placed on the body. There are many ECG monitors in the market but it is essential to find the accuracy with which they generate results. Accuracy depends on the processing of the ECG signal which contains several noises and the algorithms used for detecting peaks. Based on these peaks the abnormality in the functioning of the heart can be estimated. Hence this thesis chara… more
Date: December 2012
Creator: Ravuru, Anusha
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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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
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Synthesis and Design of Microwave Filters and Duplexers with Single and Dual Band Responses

Description: In this thesis the general Chebyshev filter synthesis procedure to generate transfer and reflection polynomials and coupling matrices were described. Key concepts such as coupled resonators, non-resonant nodes have been included. This is followed by microwave duplexer synthesis. Next, a technique to design dual band filter has been described including ways to achieve desired return loss and rejection levels at specific bands by manipulating the stopbands and transmission zeros. The concept of d… more
Date: August 2013
Creator: Mandal, Iman K.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Parameter Estimation Using Consensus Building Strategies with Application to Sensor Networks

Description: Sensor network plays a significant role in determining the performance of network inference tasks. A wireless sensor network with a large number of sensor nodes can be used as an effective tool for gathering data in various situations. One of the major issues in WSN is developing an efficient protocol which has a significant impact on the convergence of the network. Parameter estimation is one of the most important applications of sensor network. In order to model such large and complex network… more
Date: December 2013
Creator: Dasgupta, Kaushani
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Statistical Strategies for Efficient Signal Detection and Parameter Estimation in Wireless Sensor Networks

Description: This dissertation investigates data reduction strategies from a signal processing perspective in centralized detection and estimation applications. First, it considers a deterministic source observed by a network of sensors and develops an analytical strategy for ranking sensor transmissions based on the magnitude of their test statistics. The benefit of the proposed strategy is that the decision to transmit or not to transmit observations to the fusion center can be made at the sensor level re… more
Date: December 2013
Creator: Ayeh, Eric
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Development of a Cost Effective Wireless Sensor System for Indoor Air Quality Monitoring Applications

Description: Poor air quality can greatly affect the public health. Research studies indicate that indoor air can be more polluted than the outdoor air. An indoor air quality monitoring system will help to create an awareness of the quality of air inside which will eventually help in improving it. The objective of this research is to develop a low cost wireless sensor system for indoor air quality monitoring. The major cost reduction of the system is achieved by using low priced sensors. Interface circuits … more
Date: May 2014
Creator: Abraham, Sherin
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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