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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.
41

En nogrannhetsjämförelse mellan Nätverks-Rtk Och Nätverks-DGPS

Ahrenberg, Magnus, Olofsson, Andreas January 2005 (has links)
No description available.
42

Autopilot till modellbåt

Marcusson, Andreas January 2010 (has links)
No description available.
43

Indoor navigation with pseudolites (fake GPS sat.)

Eriksson, Rikard, Badea, Vlad January 2005 (has links)
This Master Thesis was conducted by Rikard Eriksson and Vlad Badea for their Master of Science degree in Electronics Design Engineering at the University of Linköping (Linköpings Universitet), Sweden. HTC Sweden AB initialized this Thesis and the Thesis contains a pre study of pseudolite based indoor navigation systems, a design of a simple pseudolite and finally some recommendations of applications. The pre study starts off with an introduction of the GPS system. This since pseudolite based systems and GPS have many similarities. Different pseudolites based techniques were then investigated and the pre study is wrapped up with a very short briefing on the Hammerhead chip. Some of the pseudolite based techniques were worth some more looking into and a pseudolite was therefore designed and simulated. There was unfortunate not enough time to actually build the pseudolite and verify it. Some recommendations to HTC Sweden were given in the last chapter of this thesis. The authors of this thesis recommend some interesting techniques and how the future work could proceed.
44

GPS-studie - Rörelsemönster inom fotboll

Andersson, Annika, Johansson, Emma January 2006 (has links)
Recent studies mostly study subjective demands for soccer players during running. However, there is a need for physioloical demands for running to make the training more effective.
45

"...det är ju så hippt att säga var man är nuförtiden. Och det gillar vi" : En jämförande studie av tidsgeografiska insamlingsmetoder

Höglund, Carina, Ivhed, Veronika January 2012 (has links)
No description available.
46

Rotocraft Low-Altitude Flight Using GPS Compass and CCD camera technique for ground object Azimuth Estimation

Huang, Kou-jen 16 July 2004 (has links)
Abstract A feasible technique, using carrier-phase data from GPS and CCD camera, is presented to identify ground target location as well as azimuth angle of a low altitude aircraft/helicopter without using any gyroscope measurements; the baseline vector can also be identified using GPS compass. The ground target¡¦s image is extracted from background and recorded by image processing technique. By integrating ground target¡¦s location and the recorded GPS data, the designated states can be estimated by using extended Kalman filter technique. Basically, the extended Kalman filter does the state estimation job, and it¡¦s a nonlinear measurement process. By processing these time update and measurement update, the integer ambiguity as well as azimuth angle can be determined. The proposed GPS compass system consists of three componets : pointer, sensor, and controller. By using carrier-phase data from two GPS receivers, we can compute the baseline vector, whose length is equal to one meter, and achieve the direction accuracy within one degree. The integer ambiguity number is resolved by rotating the baseline vector; the conventional antenna swapping technique is a special case of the proposed method. Therefore, the GPS compass may replace these magnetic compass or gyroscope used in navigation system. By continuously snapping ground target image using CCD camera and utilizing the GPS receivers, the coordinate of the ground target can be identified. Simulation justifies the feasibility of the proposed scenario. Simulation has shown that the estimation errors for stationary and traveling with constant velocity ground targets are within 1.8 m and 6 m, respectively.
47

The Bus Transportation Management System used New Bus Management Tools

Shen, Hsien-Cheng 09 August 2006 (has links)
Abstracts The Highway Bus Transportation Business to run by the local people was start in 1995. Every company attach importance to service and chair convenience. and have great advance in service and chair convenience . Transportation process was less advance include safety and process convenience. The bus transportation management importance to safety and convenience. Because of new management tools develop .We can use new tools to control transportation process in digital communication. Such as GPS¡]Global Positioning System¡^and GSM (Global System for Mobile Communications) This article is research used new management tools to develop the management system to control the bus driver behavior¡Bthe aberrance reason control¡BThe maintenance of bus¡Bdrive technological processes¡B the bus drive approach¡Bfuel control and immediateness control with GSM. This article instance a company and test the effectiveness management system. Keyword: GPS¡BGSM¡BManagement system
48

Techniques avancées de traitement du signal GPS pour les services LBS dvanced GPS signal processing techniques for LBS services /

Al Bitar, Hanaa Macabiau, Christophe. Boucheret, Marie-Laure January 2008 (has links)
Reproduction de : Thèse de doctorat : Réseaux, télécommunications, systèmes et architecture : Toulouse, INPT : 2007. / Texte en anglais. Titre provenant de l'écran-titre. Bibliogr. 95 réf.
49

Secure navigation and timing without local storage of secret keys

Wesson, Kyle D. 27 June 2014 (has links)
Civil Global Navigation Satellite System (GNSS) signals are broadcast unencrypted worldwide according to an open-access standard. The virtues of open-access and global availability have made GNSS a huge success. Yet the transparency and predictability of these signals renders them easy to counterfeit, or spoof. During a spoofing attack, a malefactor broadcasts counterfeit GNSS signals that deceive a victim receiver into reporting the spoofer-controlled position or time. Given the extensive integration of civil GNSS into critical national infrastructure and safety-of-life applications, a successful spoofing attack could have serious and significant consequences. Unlike civil GNSS signals, military GNSS signals employ symmetric-key encryption, which serves as a defense against spoofing attacks and as a barrier to unauthorized access. Despite the effectiveness of the symmetric-key approach, it has significant drawbacks and is impractical for civil applications. First, symmetric-key encryption requires tamper-resistant receivers to protect the secret keys from unauthorized discovery and dissemination. Manufacturing a tamper-resistant receiver increases cost and limits manufacturing to trusted foundries. Second, key management is problematic and burdensome despite the recent introduction of over-the-air keying. Third, even symmetric-key encryption remains somewhat vulnerable to specialized spoofing attacks. I propose an entirely new approach to navigation and timing security that avoids the shortcomings of the symmetric-key approach while maintaining a high resistance to spoofing. My first contribution is a probabilistic framework that develops necessary components of signal authentication. Based on the framework, I develop an asymmetric-key cryptographic signal authentication technique and a non-cryptographic spoofing detection technique, both of which operate without a secret key stored locally in a secure receiver. These anti-spoofing techniques constitute the remaining two contributions of this dissertation. They stand as viable spoofing defenses for civil users and could augment---or even replace---current and planned military anti-spoofing measures. Finally, I offer an in-depth case study of the security vulnerabilities and possible cryptographic enhancements of a modern GNSS-based aviation surveillance technology in the context of the technical and regulatory aviation environment. / text
50

Minimizing Interference in Simultaneous Operations between GPS and Other Instrumentation Systems

Kujiraoka, Scott, Troublefield, Robert, Fielder, Russell 10 1900 (has links)
Currently many airborne platforms (missiles, targets, and projectiles) contain multiple instrumentation systems to cover the functions of GPS and either telemetry, beacon tracking and/or flight termination. Most of these platforms are not very large, so mounting of various antennas to support these functions are physically close to each other. As a result, unwanted interference (in the form of RF coupling between them) is unavoidable. This paper will discuss the design considerations involved to minimize this interference as well as some lessons learned with its implementation.

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