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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
701

A game theoretic approach to improve energy efficiency of wireless sensor nodes / Willem Christoffel Petzer

Petzer, Willem Christoffel January 2015 (has links)
Wireless sensor networks (WSNs) are becoming increasingly pervasive in a number of applications. Due to the nature of WSNs, one of their biggest constraints is limited node energy. As WSNs grow in popularity, the prevalent issue remains to keep wireless sensor nodes alive for as long as possible, or risk disrupting the network. This dissertation develops a model based on the principles of game theory to improve the energy efficiency of wireless sensor nodes and increase the network lifetime by influencing the way routing takes place. The benefit of this model is a routing algorithm that is easily implementable and increases network lifetime by improving energy efficiency in the network. / MIng (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2015
702

Performance of the IEEE 802.11b WLAN Standards for Fast-Moving Platforms

Kasch, William T., Burbank, Jack L., Andrusenko, Julia, Lauss, Mark H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper addresses the physical and MAC layer performance of the IEEE 802.11b wireless local area networking (WLAN) standard in range-extended outdoor applications for high speed network platforms. Physical layer performance is quantified by bit error rate (BER) and packet error rate (PER) vs. range performance as well as acquisition and tracking performance considering Doppler effects caused by such high-speed platforms. This performance assessment is ascertained through the use of modeling and simulation and hardware-in-the-loop testing.
703

WIRELESS INFRA-RED SENSOR

Chaildin, Mark 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / For several decades, the military has used the Multiple Integrated Laser Engagement System (MILES) with a series of iR sensors along a belt fastened to a vehicle for training and simulation. Now, an alternative to this legacy system, a solar rechargeable battery powered wireless IR sensor is replacing wired sensors. The use of short-range RF communications network, allows the MILES sensors strategic placement about a combat vehicle without the umbilical cabling normally required for power and signal coupling from the players processing unit. The RF network operates in the 340 to 380 MHz band, has channeling capability of over 1600 channels, and coexists with the vehicles on board high-powered radios without interference. The wireless sensor implements a custom designed IR sensing amplifier, designed for maximum sensitivity and minimal power dissipation, along with advanced semiconductor IC’s for signal processing and power conversion. Solar recharging enables the sensor to operate for extended time, on a single battery that should last for years without replacement. A proprietary software protocol, developed for communication integrity, is a critical part of the overall system and supports other sensor types and control elements with low data rates for a wireless Vehicle Area Network. The system, successfully installed on several military training platforms, proves to be a viable product for military training and simulation systems for the 21st century.
704

Helicopter Slip Ring Replacement System

Adamson, Alan, Berdugo, Albert 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / Most helicopter programs require the acquisition of parameters from the rotating systems. Historically, these systems made use of electromechanical slip rings for the transfer of power, control, and data from within the helicopter's cabin to the rotating hardware. Slip rings are primarily used in dedicated instrumentation vehicles and are not commonly used in production platforms that may require instrumentation of the rotating systems for in-service load and fatigue monitoring. Additionally, the use of slip rings requires time and money to integrate the hardware and equipment into the aircraft in order to perform rotor data acquisition. The time needed to perform modifications to transmissions and drive trains plays a big factor in the increased costs of aircraft development. Less intrusive installations would minimize the need for mechanical changes and would improve the time needed to install the instrumentation. This paper describes a wireless system approach to perform the test without the slip ring, and provides performance data that validates this new method of instrumenting unobtrusively to save time and money without sacrificing data integrity.
705

DESIGN AND DEVELOPMENT OF WIRELESS FLUOROMETRY NETWORKS

Doonan, Daniel J., Wu, Mei-Su, Lee, Michael 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / This paper presents the design and development of a fluorometry sensor network with LED excitation. The design of the electronics in junction with the capability of LED excitation will significantly reduce the size and costs of the flrorometer units. The coverage and effectiveness of the sensing and monitoring capability will also be greatly enhanced by the addition of the wireless networks.
706

IEEE 1451 SMART TRANSDUCER STANDARDS: STATUS, GOING WIRELESS, AND PULLING IT ALL TOGETHER

Jones, Charles H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / There are seven parts of the Institute of Electrical and Electronics Engineers (IEEE) 1451 Smart Transducer family of standards either approved, in work, or in review. These documents are providing a nonproprietary set of standards for the implementation of smart transducers (i.e., sensors and actuators). This paper overviews these standards and their status. In particular, the IEEE P1451.5, which addresses wireless transducers, and the IEEE P1451.0, which will provide a common high level architecture for the entire family, will be discussed. A reference model, which is being used as a focus for the IEEE P1451.0, will be introduced to help show the relation between all the members of the family.
707

SPACE-TIME CODING FOR WIRELESS COMMUNICATIONS

Jensen, Michael A., Rice, Michael D. 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / Signal fading and intersymbol interference created by multipath propagation have traditionally limited the throughput on wireless communications systems. However, recent research has demonstrated that by using multiple antennas on both transmit and receive ends of the link, the multipath channel can actually be exploited to achieve increased communication throughput over single-antenna systems. This paper provides an introductory description of such multi-antenna communications systems, focusing on basic explanations of how they achieve capacity gains. Computed and measured capacity results are used to demonstrate the potential of these systems.
708

EVALUATION OF UBIQUITIOUS USE OF WIRELESS SENSOR NETWORK TECHNOLOGY IN DATA ACQUISITION AND TELEMETRY APPLICATIONS

Kenney, Joshua D., Cunningham, Chris J., Abbott, Ben A. 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Industrial wireless sensor networks can be designed to meet the strict requirements of specific distributed applications. Emerging standards have enabled the development of low-cost, lowpower sensor nodes that are quickly becoming a commodity, enabling the realization of efficient and reliable data acquisition and telemetry in many systems. Moreover, new and exciting possibilities arise from the distributed computing power of the sensor nodes, the ability to monitor and aggregate data across large arrays of sensors, and the ability to model dynamic and rugged environments that were previously beyond the reach of traditional data acquisition and telemetry systems.
709

TOWARDS FULLY AUTOMATED INSTRUMENTATION TEST SUPPORT

Jones, Charles H. 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Imagine that a test vehicle has just arrived at your test facility and that it is fully instrumented with sensors and a data acquisition system (DAS). Imagine that a test engineer logs onto the vehicle’s DAS, submits a list of data requirements, and the DAS automatically configures itself to meet those data requirements. Imagine that the control room then contacts the DAS, downloads the configuration, and coordinates its own configuration with the vehicle’s setup. Imagine all of this done with no more human interaction than the original test engineer’s request. How close to this imaginary scenario is the instrumentation community? We’re not there yet, but through a variety of efforts, we are headed towards this fully automated scenario. This paper outlines the current status, current projects, and some missing pieces in the journey towards this end. This journey includes standards development in the Range Commander’s Council (RCC), smart sensor standards development through the Institute of Electrical and Electronics Engineers (IEEE), Small Business Innovation Research (SBIR) contracts, efforts by the integrated Network Enhanced Telemetry (iNET) project, and other projects involved in reaching this goal.
710

The Range Area Network: A New Approach for Aeronautical Telemetry

Rice, Michael, Tinubi, Oluwasegun 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / The concept of a range area network dedicated to the reception of telemetry from airborne test articles is explored. The range area network consists of ground-based radios that receive telemetry packets from an airborne test article and relay those packets through the network to a data sink (e.g., the main telemetry display and processing center). The network may use either "dumb" nodes or "smart" nodes and this choice presents a trade-off involving node complexity, network bandwidth, and required RF power. Using a somewhat idealized, but nonetheless realistic example at the Edwards AFB complex and link budgets based on the emerging iNET standard, we show that a network consisting of just 6 nodes reduces the L-band airborne transmitter power to 6W and the ground-based transmitters to 3W. If the airborne transmitter is restricted to 1W at L-band, then coverage can be provided by a grid of 50 nodes.

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