Thesis (Ph. D.)--University of Oregon, 2002. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 273-292). Also available for download via the World Wide Web; free to University of Oregon users.

Made available in DSpace on 2014-06-11T19:22:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-25Bitstream added on 2014-06-13T20:09:31Z : No. of bitstreams: 1 polezel_wgc_me_prud.pdf: 1240950 bytes, checksum: 142fe3cb11a3c5af3d674c07f9b8cc46 (MD5) / Com a inclusão de novos sinais nos satélites GPS e o advento do sistema Galileo, o posicionamento por satélite entrará em uma nova era, trazendo inovações tecnológicas e científicas, principalmente nas combinações entre diferentes sistemas. Logo, verifica-se a importância de analisar a qualidade dos novos sinais, quantificando suas contribuições na acurácia do posicionamento. Visando contribuir com essa demanda, este trabalho tem o intuito de dar continuidade às pesquisas no Brasil sobre a qualidade advinda da modernização do GNSS utilizando os novos sinais transmitidos pelos satélites. O GNSS engloba o GPS, o GLONASS, o Galileo, o SBAS, o Beidou e o LAAS. Entretanto, neste trabalho apenas os sistemas GPS, GLONASS e Galileo serão abordados. Com esses três sistemas é possível realizar combinações lineares para integrá-los no posicionamento por ponto e relativo. Alguns problemas nessa combinação foram detectados com indicações de soluções para os efeitos não modelados. No que concerne aos efeitos da ionosfera, uma combinação ion-free utilizando três freqüências foi apresentada, permitindo eliminar os efeitos de primeira e segunda ordem da ionosfera. Apresenta-se também uma revisão bibliográfica do estado da arte da solução da ambigüidade utilizando esses três sistemas. Além disso, foi realizado um experimento a fim de analisar a qualidade do novo sinal L2C. Nas análises, tal como esperado, os satélites modernizados apresentaram melhores resultados do que os satélites não modernizados. Como o sistema Galileo ainda não está operacional, foi implementado no software GPSeq a interoperabilidade dos sinais GPS e GLONASS e realizadas análises comparando tais sistemas no posicionamento relativo. Além disso, comparou-se os resultados do software GPSeq com softwares comerciais. Os resultados, em alguns momento... / With the addition of new signals in GPS satellites and the advent of Galileo system, the satellite positioning will start a new era, which will require technologic and scientific innovations mainly in combinations of these systems. Therefore, analyzing the new signal quality and quantifying their contribution in the positioning accuracy are very important. Thus, this research points out the importance of continuing investigations in Brazil about GNSS modernization using the new signals transmitted by the satellites. The GNSS include GPS, GLONASS, Galileo, SBAS, Beidou and LAAS. However, in this work only GPS, GLONASS and Galileo system are taken into account. In order to integrate these three systems it is possible to accomplish linear combinations in absolute and relative positioning. Some problems in these combinations were detected and solutions for the unmodeled effects were recommended. For the ionospheric effect, an ion-free combination using three frequencies was performed. This combination can eliminate the ionosphere effects of first and second order. In this paper a bibliographical revision of the ambiguity solution using three systems is accomplished. Furthermore, an experiment was carried out to analyze... (Complete abstract click electronic access below)

This diploma project is about designing a concept of an anti-theft tracking device for a bicycle. The device is equipped with a GNSS module for tracking of current location, GSM module for sending the location data in case of a theft and a BT module for user settings via mobile phone. The bike theft detection is detected by an accelerometer. The final goal of this project is a concept of such a device for evaluation and improvement purposes.

This master thesis describes the principles of the Global Navigation Satellite System GNSS, specifically the GPS, GLONASS and Galileo systems. The thesis analyzes the structure of individual GNSS subsystems and introduces their properties. The algorithm for calculating the position is designed in the interactive programming environment MATLAB for the processing of GPS and GLONASS sampled signals. The position is calculated by a distance measurement method which searches for the intersection of spherical surfaces. The calculation is designed for four satellites and when more satellites are detected, the calculation is repeated for all possible combinations. From this position the combination with the lowest DOP (Dilution of Precision) factor is determined, and the calculation of the position is repeated for the best constellation of satellites. In this thesis the user graphical interface for entering the input of data, input parameters and the display of calculated values are created. Finally the calculation of the measured data is displayed on the selected location online map portal

The thesis objective is design of methodology focused on accuracy measurement in field of GPS/GLONASS receivers. Text is devided into five main parts. The first one is focused on GNSS technology. Second one deals with used coordinate systems and map projections (ETRS89, WGS84, UTM, Gauss-Krüger). Next part discusses statistical methods. Part four is focused on hardware. Then the final part describes experiment realization and obtained data analysis.

In order to directly interface with signal broadcast by global navigation satellite systems (GNSS) – such as GPS or Galileo – for the purpose of calculating location, a potential user is required to extract great amount of information from interface control documents (ICD) as well as build custom software tools to process this information. This is time consuming and inefficient. Instead it would be great if such tools and information was readily available in one single project. This thesis addresses this issue by designing a universal data structure which is able to accommodate all necessary information to interface with any GNSS. Universal GNSS data structure is designed in such a way so that software tools can be entirely generic across all GNSS, i.e. do not include any functionality specific to only one GNSS. This is done by embedding certain logic parameters inside data structure itself, which determine how software tools behave. The data structure realized in the form of XML file with specific rules and syntax. Data from GPS and Galileo ICDs is scraped and compiled into XML file. A Rust tool-set is created to read XML file and extract information such as pseudo-random noise codes and navigation message structure. Using this information, it is possible to decode a raw bit stream broadcast by GNSS spacecraft, although currently additional tools need to be added to completely automatize this process.

GNSS positioning has become a key element in everyday life of millions of people, from the person using google maps to move around an unknown city to the mailman or the DRON pilot who require it to carry out their work. All of them benefit in some way from the GNSS constellations and the position algorithms.The European Union through their GNSS constellation, Galileo, has recently made available a new service called Galileo High Accuracy Service (HAS). With the aim of improving the positioning solutions already provided by the Open Service (OS) to a centimetric level with the target of professional and commercial users requiring this high accuracy. As a result, in this Master Thesis project the steps of the development and implementation of a Software-Defined Radio to collect the High Accuracy corrections transmitted through Galileo GNSS constellation are going to be shown. The SDR itself is going to be made available so that other persons from companies to academia can benefit from it and see how the corrections are extracted and either use the algorithm or implement its own to be able to use this High Accuracy Service.

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Galileo är ett europeiskt system med global täckning som idag utgörs av ca tio operativa satelliter. Systemet utökas successivt och beräknas vara fullt operativt runt år 2020. Fyra nya satelliter är planerade att aktiveras under 2017 och ytterligare fyra satelliter kommer att skjutas upp under 2017.  Syftet med studien har varit att testa tillgängligheten och osäkerheten i Galileo mot SWEPOS i en multi-GNSS-konstellation. Där målet har varit att visa vilka fördelar Galileo kan bidra med vid satellitpositionering i Network Real Time Kinematic (Nätverks-RTK) under tuffare mätförhållanden.   Nätverks-RTK mätningar har genomförts för att studera förbättringar Galileosignaler kan bidra till i olika utmanande miljöer. Mätningar har utförts i två typer av miljöer, skogsmiljö där träd stör och blockerar satellitsignaler och även i urban miljö där höga byggnader och fordon kan störa signaler och orsaka fel. Mätningarna har utförts över punkter med kända koordinater i Gävle stad och Mårtsbo. Flera mätningar har gjorts över varje punkt, en mätning varje sekund i 60 sek, vilket möjliggör 60 observationer. Denna procedur har gjorts flera gånger med elevationsvinklarna 15, 25 och 35°. SWEPOS, det permanenta GNSS-nätverket i Sverige har använts vid genomförandet av nätverks-RTK-mätningarna. SWEPOS är ännu inte kompatibelt med Galileo, därför har tillfälliga SWEPOS-referensstationer som stöder Galileo använts. Mottagaren och den handhållna enheten som används under mätningarna har varit från tillverkaren Trimble. GNSS-planering har använts för att se till att det alltid funnits Galileo-satelliter tillgängliga under mätningarna. Studien visade att för att kunna se fördelarna med Galileo under nätverksRTK måste elevationsvinkeln sättas högre än 15°. Detta begränsar antalet satelliter som tillhör Globalnaya Navigatsionnaya Sputnikovaya Sistema (Glonass) och Global Positioning System (GPS), vilket kan visa fördelarna med Galileo. På vissa punkter som använts för mätningarna var det inte möjligt att få fixlösning utan Galileosignaler.  Slutsatsen av studien är att Galileo med få satelliter kan bidra till en högre satellittillgänglighet, en högre chans till att uppnå fixlösning och minimera tiden för att uppnå fixlösning vid användning av en hög elevationsvinkel eller i tuffa miljöer.

De nombreuses représentations de Galilée évoquent un conflit entre lui et l’Église catholique : Galilée devient le symbole de l’opposition entre la science et la religion. Or, dans la Lettre à Christine de Lorraine, Galilée propose une réflexion à propos de l’interprétation des Écritures dans un contexte de philosophie naturelle. Après avoir présenté une synthèse de cette Lettre ainsi que le contexte de rédaction, il sera possible de l’interpréter à partir d’une typologie de l’articulation des discours religieux et des discours scientifiques et ce, dans le but de caractériser les rapports "science et religion" développés par Galilée. La typologie sera ici un outil herméneutique permettant de déceler ces rapports à partir de catégories prédéfinies (conflit, indépendance, complémentarité, intégration). Il apparaîtra que Galilée présente plusieurs types de rapports « science et religion ». Cette approche a l’avantage de développer une interprétation originale de la Lettre.