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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.
171

Design and Implementation of a Practical Aircraft Position and Reporting Identification Beacon (PRIB)

Lee Yan, Yuen On 11 July 2003 (has links)
A transponder is a device that is used for tracking aircraft by mean of a secondary radar system, but it can be turned off deliberately, and it is an expensive item for small aircraft. These weaknesses have fatal consequences, as was shown with the terrorist attack on September 11 th , 2001, where four commercial aircraft under the control of international terrorists were used as missiles against the United Stated of America, killing thousands of people. These factors have shown a need for the development of an efficient aircraft tracking system, which does not rely on transponders. To this end a new tracking aircraft system is proposed, which will be referred to as the Positioning and Reporting Identification Beacon (PRIB) system. Due to size, mass, power, and financial constraints, the design must be small, light, power efficient, and cost-effective. The PRIB will acquire the aircraft's position from a dedicated GPS receiver and then transmit this information to a base station at a different location using a radio link. This thesis presents the design of a PRIB unit in light of the system constraints. In addition to the hardware design, the software needed by the unit to control and communicate with the ground stations is presented. The performance of the PRIB is analyzed and ways in which a PRIB could be manufactured using commercial off-the-shelf parts is discussed. / Master of Science
172

In-rest Vehicle GPS Proximity Warning in Surface Operations

Miller, Stephen J. 06 January 2006 (has links)
Proximity Warning Systems are currently the focus of many research groups. Their goal is to produce a system that will reduce the number of run over incidents that occur in large mobile equipment operations. A majority of these incidents occur when the equipment starts from the In-rest state and begins to move. The addition of a transmission locking mechanism to a GPS based proximity warning system will prevent more run over incidents. This transmission locking mechanism will automatically prevent equipment from moving when there is a high risk for a potential run over incident to occur. Additional safety and optimization for surface equipment can be provided by utilizing GIS software for data analysis just by using the data collected from a GPS based proximity warning system. Combining these ideas and methods can provide better safety for large mobile equipment operations. / Master of Science
173

STUDY ON OEM-BASED DIFFERENTIAL GPS

Shengxi, Ding, Qishan, Zhang, Xianliang, Li 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Two kinds of differential GPS (DGPS) technology on position differential GPS and pseudo-range differential GPS are studied and compared in this paper. Positioning tests by single GPS receiver, position DGPS and pseudo-range DGPS systems based on GPSOEM board are done. Experiment result indicates that position error is about 30 - 100 meters on single GPS receiver and position error is reduced to 3 - 10 meters on DGPS. Furthermore, Developed DGPS system which is based on GPS-OEM has the advantages of low cost, utility and flexibility, etc.
174

AN INTEGRATED GPS TRACKING AND TELEMETRY SYSTEM FOR RANGE APPLICATIONS

Wells, Lawrence L., Montgomery, Robert S. 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / This paper describes a highly integrated and low cost GPS Translator/Telemetry system for use on missile platforms – the Digital GPS Translator (DGT), a component part of the Translated GPS Range System (TGRS). The DGT provides translated GPS tracking capability combined with transmission of telemetry at rates of up to 10 Mbps with optional encoding and/or encryption. This integrated approach to GPS tracking and telemetry results in a significant reduction in hardware size and cost compared to a segregated approach. The TGRS includes a ground-processing unit that provides real time processing of both the GPS and telemetry portions of the DGT transmission.
175

Satellitengestützte Fahrzeuglokalisierung in urbanen Gebieten mit GPS und GLONASS

Reisdorf, Pierre 19 July 2012 (has links) (PDF)
Navigationssysteme sollen nach Möglichkeit an jedem Ort und zu jeder Zeit funktionieren. Satellitennavigationssysteme unterliegen jedoch gewissen äußerlichen Einschränkungen, die die Positionierung erschweren oder erheblich verschlechtern. In einem urbanen Gebiet sind die Einflüsse auf die Positionierung mit Satellitensystemen durch die eingeschränkten räumlichen Verhältnisse besonders groß. Sowohl Mehrwege-Effekte wie auch die Verkleinerung des Sichtbereiches zu den Satelliten treten deutlich mehr auf. Mit der Verwendung von mehreren Satellitensystemen soll versucht werden, die Positionierung im urbanen Gebiet zu verbessern oder überhaupt erst möglich zu machen. Zur Untersuchung werden dafür die Eigenschaften Verfügbarkeit, Genauigkeit und Integrität für GPS, für GLONASS und für beide Systeme als ein Gesamtsystem genauer betrachtet.
176

Konstrukce GPS přístroje / Construction of The GPS device

Hlaváč, Libor January 2010 (has links)
The goal of this thesis is a complete design and realization of a device that is able to communicate with GPS module iTrax300 and display the coordinates received from the module. The thesis deals with the GPS, localization principles and the standard communication protocol for navigation systems - the NMEA 0183 protocol. Futhermore it is dealing with the particular steps in the realization of the engineered device (from the specification of requirements at the beginning to the testing of its functionality in the end). The GPS coordinates, the Coordinated Universal Time (UTC), the date, the altitude and the speed on the ground can be displayed. There is also a possibility to put in any coordinates, the direction and the distance to the point are displayed afterwards. The device enables the track storage in the memory as well. The track is viewable while connecting the device and the PC through the USB interface.
177

Global Positioning System Clock and Orbit Statistics and Precise Point Positioning

Cohenour, John C. 18 September 2009 (has links)
No description available.
178

Analysis of water level measurements using GPS

Cheng, Kai-chien 07 October 2005 (has links)
No description available.
179

Signal Acquisition and Tracking for a Software Gps Receiver

Zheng, Sophia 31 March 2005 (has links)
Global Positioning System (GPS) is a satellite-based navigation system that has been used widely both in civilian and military for positioning, navigation, timing and other position related applications. The hardware-based GPS receivers provide the least user flexibility. Thus, it is necessary to have Software-based GPS receivers for easy and quick implementation, simulation and analysis of algorithms. Software-based GPS receiver processes the GPS signal at the radio frequency or intermediate frequency depending on the hardware configuration of the receiver. In this development of the acquisition and tracking processes of the software receiver, the front-end device that converts the radio frequency signal from the antenna to an intermediate frequency is the Mitel 2021 GPS receiver board. An analog-to-digital (A/D) converter then digitizes the output signal from the RF front-end. The data is then processed using MATLAB programs to achieve acquisition and tracking of the GPS signals. The software GPS receiver can perform acquisition and tracking using different parameters and threshold values. This flexibility of operation allows weaker signals to be tracked and processed. In this software receiver design, the focus is on the acquisition and tracking of L1 band C/A code GPS signals used by most civilian applications. The purpose of this thesis is to develop the acquisition and tracking algorithms to extract the navigation data bits from the raw GPS signals. The navigation data bits provide all the necessary information to compute the pseudorange between the receiver and the visible satellites and determine the receiver location. Both MATLAB simulated GPS data and realistic GPS signals from a GSS 6560 simulator are used to verify the performance of the acquisition and tracking programs. The acquisition program is capable of locating the beginning of the C/A code and the carrier frequency to within the desired accuracy. From the output of the acquisition program, the tracking program can decode the navigation data bits. The tracking algorithm implemented is based on the block adjustment of synchronizing signal (BASS) method. / Master of Science
180

Proposta de metodologia para melhora do posicionamento obtido através de receptores GPS de baixo custo. / Proposal of a methodology for improving low cost GPS receivers positioning.

Lima, Erly Caldas de 08 May 2018 (has links)
O desenvolvimento técnico da eletrônica, a contínua redução do tamanho dos receptores GNSS, associada à diminuição do consumo de energia, transformaram estes produtos em alguns circuitos integrados ou apenas pequenos chips do tamanho de um botão de uma camisa. Desta forma pode-se promover a sua integração com inúmeros dispositivos eletrônicos. A associação com os telefones celulares foi principalmente impulsionada pelo mandato de aprimoramento dos serviços 911 (E911) da Federal Communications Commission (FCC) nos Estados Unidos, exigindo que todas as operadoras de telefonia móvel daquele país fornecessem a localização com boa precisão das chamadas de emergência. Esta necessidade estimulou a produção dos chips em larga escala e, portanto, a diminuição do custo e a sua popularização. Desta maneira quase que em sua totalidade, os telefones celulares são hoje fabricados com receptores GPS, o que torna estes dispositivos uma das fontes mais baratas de se obter o Geoposicionamento. Acontece que existe uma lacuna na literatura quanto à precisão e a exatidão das coordenadas fornecidas por estes equipamentos. O presente trabalho visa, através de testes estatísticos e da comparação com outros receptores GPS e métodos, quantificar estes valores e propor uma metodologia para melhorar tal posicionamento. Para conseguir o objetivo, a estrutura do Sistema Operacional do telefone foi modificada de tal modo que fosse possível o acesso às observáveis do chipset do GPS embarcado e convertidos para o padrão RINEX de arquivamento de dados brutos. Os testes foram executados com o equipamento original e com o equipamento modificado com a instalação de uma antena externa e mostraram que com a utilização da medida de fase da portadora o equipamento pode fornecer o posicionamento com uma precisão média de 0,069m, com o desvio padrão de 0,047m e erro planimétrico de posicionamento máximo de 0,218m e mínimo de 0,004m. / The technical development of electronics, the continuous reduction in the size of GNSS receptors, allied with the energy consumption decrease, transformed these products into some integrated circuits or in small Chips as small as size of a button of a shirt. In this way one can promote its integration with countless electronic devices. The association with cell phones was mainly driven by the mandate to enhance services 911 (E911) of the Federal Communications Commission (FCC) in the United States, requiring that all mobile carriers of that country provide all the emergency calls location with good accuracy. So as to fulfill this necessity, the production of Chips in a large scale has been stimulated and therefore the decrease in cost and its popularity. In this way almost in its entirety, cell phones are now manufactured with GPS receivers, which makes these devices one of the cheapest sources to obtain the geopositioning. It turns out that there is a gap in the literature about how precise and accurate the coordinates provided by these equipments can be. This thesis aims through statistical tests and comparison with other GPS receivers and methods, quantify these values and propose a methodology to improve such positioning. To achieve the objective, the structure of the phone\'s operating system was modified in such a way that it was possible to access the embedded GPS Chipset observables and then converted into the RINEX standard raw data file. The tests were carried out with the original equipment and with the modified ones, with an external antenna installation which showed that using the phase measure of the carrier, the equipment can provide a positioning with an average accuracy of 0, 069m, with a default deviation of 0, 047m and a maximum planimetric positioning error of 0, 218m and a minimum of 0, 004m.

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