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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.
1

A 3D LINK ANALYSIS AND SELECTION OF A RECEIVE ANTENNA ANGLE IN TELEMETRY SYSTEMS

Jang, Dhong Woon 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / A three dimension (3D) link analysis is performed considering multipath effects caused by a reflected signal and the difference angle between the antenna bore-sight and Line-Of-Sight (LOS). In addition, a direction of a receive antenna is determined for a receiver to get maximum signal strength in a telemetry situation. For a fixed receive antenna, the angle is determined to maximize the average Carrier to Noise Ratio (CNR) over the interested part of a trajectory. For a tracking antenna, the angle at every position is selected to give maximum CNR or to direct the boresight to the flying projectile.
2

Ultra Wideband Ranging and Link Budget Design for Naval Crane Applications

Volos, Haris I. 28 July 2006 (has links)
In this thesis a UWB-based ranging scheme is designed, simulated, implemented and tested. This system was designed to address the problem of safely unloading cargo crates to ships in the open seas. UWB antennas are placed on the four corners of the cargo crate, providing the information needed to a ranging/positioning algorithm that estimates the orientation and distance of the ship's deck from the crate. Furthermore, the system is successfully tested in a 1/24 scale demonstration. In addition to the UWB ranging application, this thesis evaluates an already proposed modification to the traditional narrowband link budget based on the Friis transmission formula. The proposed modification replaces frequency-domain parameters with time-domain values to handle the wide bandwidth of UWB systems. The proposed approach is shown via measurements to be much more accurate than the traditional technique. / Master of Science
3

FLIGHT TESTS OPTIMIZATION BY SATCOM BASED TELEMETRY LINK

Rodrigues, Tiago Giglio, Góes, Luis Carlos Sandoval, Leite, Nelson Paiva Oliveira, Marins, Carlos Nazareth Motta 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The terrestrial microwave telemetry links show limitation due their inherent features concerning bandwidth availability, frequency allocation and range. Also it supports only one aircraft per test and the data acquisition capacity can be enhanced. Following the flight tests trends, it proposes a telemetry link based on satellite communications deployed by off the shelf equipments allowing advantages as bandwidth availability, multiple aircrafts telemetry and almost global range into the reliability standards. By simple equations and typical flight tests data it demonstrates the feasibility of the telemetry system proposed for time and costs reduction to optimize flight tests programs.
4

Radio Resource Management in WiMAX

Shabbir, Noman, Kasif, Hasnain January 2009 (has links)
Today, different types of cellular networks are actively working on the radio links. For instance, the Global System for Mobile Communication (GSM) is being used in nearly two hundred countries and currently it has around two and half billion users all over the world. Universal Mobile Telecommunication System (UMTS) is currently deployed in many countries and it is providing increased data rates, coverage and mobility as compared to GSM. Wireless Local Area Networks (WLAN) are very famous when we have a small area and none real time services. Worldwide Interoperability for Microwave Access (WiMAX) is a new technology and it is in deployment phase. In all these cellular technologies, we have very limited recourses and we have to make best use of them by proper management. Radio Resource Management (RRM) is a control mechanism for the overall system which is being used to manage radio resources in the air interface inside a cellular network. The main objective is to utilize the available spectral resources as efficiently as possible. Our aim is to use them in the best possible way to maximize the performance and spectral efficiency in such a way that we have maximum number of users in our network and Quality of Service (QoS) is up to the mark. In a cellular communication system, a service area or a geographical region is divided into a number of cells and each cell is served by an infrastructure element called the base station which works through a radio interface. The frequency license fees, real estate, distribution network and maintenance are the issues which dominates the cost for deploying a cellular network. Management of radio related resources is a critical design component in cellular communications. In RRM, we control parameters like Radio Frequency (RF) planning, link budgeting, modulation schemes, channel access schemes etc. RF planning includes cell planning, coverage of the network and capacity of the network. Our main focus in this thesis will be on cell planning and link budgeting and we will discuss them in context of a WiMAX network.
5

Development of IEEE 802.11b RF Transceiver Modules

Han, Fu-Yi 10 July 2003 (has links)
This thesis consisted of three parts. Part 1 introduced the design procedure of an RF transceiver modules for IEEE 802.11b WLAN system. It contained the selection of RF architectures, frequency planning, and the receiver link budget analysis flow. Part 2 focused on the implementation of each stage in the whole RF link. The design considerations of choosing passive elements and the parasitic effect of the evaluation board are discussed. Part 3 integrated the whole RF transceiver module and estimated the performance of this module through the link budget analysis method. Furthermore, a complete specification measurement was accomplished by using the standard test signals. The test results confirmed with the budget results, and also pass the specification of IEEE 802.11b WLAN system.
6

Estudio y simulación de cobertura VoLTE mediante diseño de link Budget para red 4G LTE de Entel de Santiago

Apablaza de la Cuadra, Alexis Andrés January 2017 (has links)
Ingeniero Civil Eléctrico / Entel S.A., la mayor empresa de telecomunicaciones móviles de Chile, requería evaluar el impacto que tendría la incorporación del servicio Voice Over LTE (VoLTE) en su red 4G de datos, en Santiago, con el fin de estimar la inversión requerida en caso de que existiera disminución de cobertura del servicio. Dado lo anterior, el objetivo del presente trabajo de título se enfocó en determinar el área de cobertura que tendrá la actual red 4G de Entel al incorporar el servicio VoLTE. Para llevar a cabo esta tarea se diseñó un Link Budget de VoLTE, el cual se utilizó posteriormente para determinar los puntos de corte en simulaciones que se realizaron en el programa Mentum Planet. De esta forma, se comparó la cobertura de la red de datos (Best Effort) con la cobertura VoLTE. La metodología utilizada en el desarrollo de la presente memoria comprendió la investigación y el análisis de redes móviles LTE, desarrollando y plasmando en el segundo capítulo, una base teórica que permite un amplio y fácil entendimiento de éstas para cualquier persona. Posteriormente, comprendió el diseñó del Link Budget de VoLTE, el cuál fue generado en un documento Excel, otorgando de esta forma una herramienta sencilla y útil al área de optimización de redes de acceso de Entel. El trabajo concluyó con la realización de sets de simulaciones en el programa solicitado, con lo que se obtuvo los porcentajes de cobertura asociados tanto a la red Best Effort como al servicio VoLTE, para las bandas de frecuencia de 2600 MHz y 700 MHz. Entre los principales resultados del presente trabajo, cabe destacar: 1. Disminución aproximada de un 7.5% de cobertura para el servicio VoLTE en comparación a la cobertura del servicio de datos Fourth Generation of Wireless Telephone Technology (4G), para la banda 2600 MHz, considerando Reference Signal Received Power (RSRP) de corte sin fading. 2. Disminución aproximada de un 19% de cobertura para el servicio VoLTE en comparación a la cobertura del servicio de datos 4G, para la banda 700 MHz, considerando RSRP de corte sin fading. 3. Se confirma la importancia del feature TTI Bundling para mejorar la cobertura del enlace ascendente, estableciendo una mejora entre un 20 y un 25% en la cobertura. Como consecuencia final, el presente trabajo entrega a Entel una cuantificación de la cobertura esperada, así como un conjunto de recomendaciones para la implementación del servicio VoLTE, y de ésta forma, pasar a la etapa de evaluación económica para la implementación definitiva del proyecto.
7

REAL TIME C BAND LINK BUDGET MODEL CALCULATION

Rubio, Pedro, Fernandez, Francisco, Jimenez, Francisco 11 1900 (has links)
The purpose of this paper is to show the integration of the transmission gain values of a telemetry transmission antenna according to its relative position and integrate them in the C band link budget, in order to obtain an accuracy vision of the link. Once our C band link budget was fully performed to model our link and ready to work in real time with several received values (GPS position, roll, pitch and yaw) from the aircraft and other values from the Ground System (azimuth and elevation of the reception telemetry antenna), it was necessary to avoid a constant value of the transmitter antenna and estimate its values with better accuracy depending of the relative beam angles between the transmitter antenna and receiver antenna. Keeping in mind an aircraft is not a static telecommunication system it was necessary to have a real time value of the transmission gain. In this paper, we will show how to perform a real time link budget (C band).
8

VHF & UHF energy harvesting radio system physical and MAC layer considerations / VHF and UHF energy harvesting radio system physical and MAC layer considerations

Zhang, Xiaohu January 1900 (has links)
Master of Science / Department of Electrical and Computer Engineering / William B. Kuhn / Wireless Sensor Network industrial and civilian applications have been moved closer to us since they were originally developed for defense applications. They have been or will be widely used in industrial process monitoring and control, earth quake monitoring, healthcare applications, construction health monitoring, home automation, traffic control, and space exploration. The IEEE802.15.4 standard defines the PHY and MAC layers for low power wireless sensor networks. However, applications and research of wireless sensor networking are centered on battery powered devices. To remove the battery from the system is the ultimate goal of this research by using Energy Harvesting technology, which will largely reduce the wireless sensor network maintenance cost, increase the option open to application environments and push the speed of wireless sensor network industrialization. This thesis tackles the problem of RF link budget and PHY layer design for Energy Harvesting Wireless Sensor Network Nodes, through a modification to PHY/MAC layers. To this end, a prototype of energy harvesting radio is developed that hinges on burst-communication and solar cell energy harvesting techniques. The choice of operating frequency is considered relative to transmission range, antenna technology and RF link budget, and quantified by propagation measurements at four unlicensed frequencies in the VHF through UHF spectrums. A short preamble, PHY payload protocol frame structure and synchronization method are also proposed in order to support long sleep period duty cycle necessary in Energy Harvesting Radio systems. Some related work has recently begun under a standardization effort known as 802.15.4f. It is hoped that this thesis will contribute to this effort.
9

Case Study: Conceptual Ground Station Design for N66 Connect AB

Rijal, Samundra January 2017 (has links)
As the communication deficit in the Arctic region is enormous especially above 75 [Deg] N latitude, the concern and opportunity of providing reliable & efficient connectivity in the Arctic region has beenduly noted & understood by N66 Connect AB (N66). This case study documents a comprehensive research which implements system engineering approach for establishment of a Ground Station (GS) at Svalbard, Norway with sole focus of connecting the inaccessible geographical region lying in the Arctic with rest of the world. Several GS system & subsystem are studied and comparative analysis is made on how the communication can be established with the N66 Connect AB (N66)’s potential clients and its satellites that are to be deployed in September, 2018.The case study resulted in analysis of several risks involved during development & operation of the GS,the hardware, software & operational architecture, the features of GS’s system capable of meeting N66’s objectives and the market potential of the service after GS operations.
10

Blue Cool Connectivity box

Aerva, Manasa Reddy, Devendra Venkata Sai Mani, Chakradhar Ghantasala January 2017 (has links)
The invention of closed circuit television (CCTV) has initiated a new trend in high security by video surveillance. More recently, CCTV cameras have been incorporating wireless LAN technology for data transfer purposes by using on chip memory storage until the time of update. In this thesis, short range communication such as Bluetooth low energy (Bluetooth smart) is used in order to perform simple I/O applications. The two important components of the project are the camera and the Bluetooth module box. An external antenna is designed for the connectivity box and the operating range of the box is deduced by using link budget. The blue cool connectivity box is assessed by defining the capabilities of the box, i.e., simple I/O operations. Field test measurements for the designed antenna provide optimum communication range. The thesis also reviews software simulation tools that are essential for antenna design and path loss modelling. The efficiency of simulated measurements versus real-time measurements are also assessed. The primary target of the thesis is to detail the design of a cost-effective antenna based on link budget calculations and perform basic I/O tasks wirelessly between the blue cool connectivity box and the camera. It is concluded that in future works, advanced operations can be added on to the existing model. It is also suggested that a model for multi floor communication can be designed.

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