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The wide spread of GPS devices capable of recording motion tracks has provided a huge amount of GPS track data with lots of information that can be used in various ways. Typical use of the data is to visualize the trajectory, but this is certainly only elementary use of the data. Additional processing, filtering and altering of data can significantly improve their information value. For example identification of popular places or routes, detection and removal of inaccurate parts of tracks, accenting speed or elevation progress on track, etc. The aim of the thesis is to identify and describe best solutions to process and visualize GPS track datasets. That means analysis of a standalone track, mutual comparison of several tracks or identification of characteristics of a large tracks set. The thesis will include a prototype implementation of selected described methods.

The majority of navigation satellite receivers operate on a single frequency and experience an error due to the ionospheric delay. They compensate for the ionospheric delay using an ionospheric model which typically only corrects for 50% of the delay. An alternative approach is to map the ionosphere with a network of real-time measurements, with either a thin shell approximation or a full 3D map. Here, a time-dependent 3D tomographic imaging technique is used to map the free electron density over the full-height of the ionosphere during solar maximum. The navigation solutions computed using corrections based upon models and thin-shell and full-height maps are compared in this project. The models and maps are used to calculate the excess propagation delay on the L1 frequency experienced by GPS receivers at selected locations across Europe and North America. The excess delay is applied to correct the pseudo-range single frequency observations at each location and the improvements to the resulting positioning are calculated. It is shown that the thin-shell and full-height maps perform almost as well as a dual-frequency carrier-smoothed benchmark and for most receivers better than the unfiltered dual-frequency benchmark. It is also shown that the unfiltered dual-frequency method is not reliable, which is of concern as it is a proposed upgrade to current positioning systems. The improvements in positioning accuracy vary from day to day depending on ionospheric conditions but can be up to 25m during mid-day at solar maximum conditions at European mid-latitudes. The full-height corrections perform well under all geomagnetic conditions and are considerably better than thin-shell corrections under extreme storm conditions. The transmission of the navigation correction requires a forecast, an image compression and a system of distribution across a local region. The feasibility of this is demonstrated for regions of land and near-land coastal regions across Europe.

Le Global Positioning System (GPS) a de nombreuses applications scientifiques. En géophysique de précision, il est utilisé pour déterminer les mouvements des plaques tectoniques, quantifier la déformation aux frontières des plaques ou dans le domaine intraplaque, ou bien détecter les signaux transitoires associés au cycle sismique. Aujourd'hui, la surface du globe est recouverte de milliers de stations GPS permanentes permettant de générer les séries temporelles de coordonnées de stations GPS et de suivre en continu les mouvements de l'écorce terrestre. Mon travail de thèse se situe dans le contexte du développement de grands réseaux GPS et GNSS (Global Navigation Satellite System) permanents. Par exemple, le réseau GEONET (GNSS Earth Observation Network System) du Japon comprend plus de 1000 stations, le réseau du Plate Boundary Observatory comprend lui aussi environ 1200 stations dans l'ouest des États Unis. A une échelle plus locale, les réseaux permanents en Europe possèdent environ 300 stations, et celui de Taïwan, plus de 400 stations. Des nombreuses difficultés se posent en pratique pour réaliser des séries temporelles précises et analyser les solutions de ces grands réseaux GPS permanents. Une première difficulté réside dans l'expression des solutions journalières dans un repère précis et stable dans le temps. Le grand nombre de points et la longueur des séries temporelles maintenant disponibles rendent les calculs lourds en temps. Des erreurs dans les solutions journalières ou dans la solution de référence peuvent biaiser l'estimation des paramètres de la transformation et dégrader la précision des séries temporelles obtenues. A l'étape de l'analyse des séries temporelles, on rencontre fréquemment plusieurs problèmes causés soit par des causes artificielles ou des mouvements géophysiques parfois complexes. La détection de ces problèmes et leur résolution dans les séries temporelles GPS de plus d'une décennie d'observation par une approche manuelle n'est plus possible et des algorithmes d'analyse automatique doivent être développés. L'objet de ma thèse est de déterminer des approches, des méthodes et des algorithmes robustes permettant (1) la réalisation rapide et précises de séries temporelles de position (2) l'identification rapide des problèmes présents dans les séries temporelles GPS (3) la résolution automatique des problèmes les plus courants (4) la manipulation facile des séries temporelles pour extraire les paramètres utiles aux analyses géophysiques. Dans ce travail, je présente tout d'abord une approche basée sur la norme L1 pour estimer les paramètres de transformations des solutions libres vers une solution de référence. Ensuite, je présenterai différents algorithmes de recherches automatiques d'erreurs et de détection, estimation, corrections des sauts. Enfin, je montrerai comment ces algorithmes peuvent être utilisés dans un modèle général des séries temporelles pour obtenir une analyse automatique et par exemple, extraire les paramètres des déformations co- et post-sismiques. Les essais méthodologiques ont été en premier lieu testés sur le réseau national GPS permanent français RENAG et une solution combinée des réseaux GPS de Taïwan. Ces deux applications permettent d'évaluer la capacité des méthodes développées à obtenir des vitesses précises et modéliser des mouvements complexes liées au cycle sismique. / The development of the Global Positioning System (GPS) allows numerous applications in Science. In high precision geophysics, GPS is used to determine the motion of tectonic plates, to quantify the plate-boundary and intra-plate deformations, and detect the time variable deformation associated with the seismic cycle. Today, the Earth’s surface is covered with thousands of permanent GPS stations allowing to generate the position time series of GPS stations and continuously monitor the earth’s crust displacement. My thesis takes place in the context of the development of large permanent GPS networks. For example, the Japan GEONET (GNSS Earth Observation Network System) network includes over 1000 stations, the Plate Boundary Observatory (PBO) network that includes about 1200 stations in the western United States. At a smaller scale, the GPS permanent network in Europe comprises about 300 stations, and in Taiwan more than 400 stations. The analysis of permanent GPS networks faces many difficulties mainly that falls into two categories: at the step of transformation of the free daily solutions into the reference solution (reference frame definition), the large number of points and length of the time series makes the calculation time consuming. It is furthermore subject to errors in either free or the reference solution, possibly biasing the transformation parameters estimates and ultimately decreasing the accuracy of final time series. At the step of GPS time series analysis, either artificial or geophysical signals can cause non-linear motion, offsets causing bias in the estimated velocities. The detection of these problems and their resolution in the GPS time series with decades of observations with a manual approach is difficult, if not impossible. The subject of my thesis is to define rapid and robust approaches, methods and algorithms for (1) the rapid determination of time series, (2) the identification of problems in the derived time series (3) the automatic resolution of most common problems, (4) the easy manipulation of time series enabling the user extract the parameters useful for the geophysical analysis, for instance the co- and post-seismic displacements. The methodologies developed are tested using the solutions for the RENAG network (French National GPS Network) and the GPS Taiwan network. The first analysis aims at assessing the capability to derive high precision velocity, while the Taiwan network defines a good test case to extract and modelize signals associated with the earthquake cycle.

Optimal missile guidance and flight performance require accurate and continuously updated in-flight coordinate data. The Global Positioning System (GPS) is used for this positional awareness. However, due to missile rotation and orientation variations during flight, GPS signal reception using traditional antennas may be intermittent. To remain cost competitive, Stellar Exploration Inc. is developing a low-cost omnidirectional GPS antenna for guided missile prototypes. In this thesis, existing products and design techniques are examined, design constraints for supersonic missile applications are investigated, and corresponding performance goals are established. A conformal microstrip patch antenna is developed and simulated in Agilent’s Advanced Design System (ADS). The resulting antenna is constructed and characterized. Prototype testing verifies that the antenna maintains GPS signal lock regardless of orientation. The final cost is significantly lower than existing conformal products. A second revision investigates enhanced modeling, dimensional reductions (via increased dielectric constant), and radome construction. Performance is compared to first revision antenna results and differences are examined. Suggestions for further revisions are discussed.

Angstverhalten bei der Panikstörung mit Agoraphobie wird hauptsächlich unter dem Aspekt des „safety seekings“ betrachtet. Kontrovers diskutiert wird, ob diese Verhaltensweisen für eine erfolgreiche Behandlung abgebaut werden sollen. Es wurde bisher kaum nach der ethologischen Bedeutung bestimmter Verhaltensweisen unter Angst gefragt. Dies ist erstaunlich, weil die Panikstörung mit Agoraphobie häufig als gesteigerte Form extraterritorialer Angst gesehen wird. Extraterritoriale Angst tritt typischerweise bei Tieren auf, wenn sie ihr vertrautes Gebiet verlassen. Im Tiermodell liegen zahlreiche ethoexperimentelle Paradigmen vor, mit denen man das natürliche Angstverhalten von Tieren untersucht. Letztlich klärt man am Tiermodell aber Fragestellungen, die am Menschen nicht umsetzbar sind. Die experimentelle Untersuchung menschlichen Angstverhaltens unter ethologischer Perspektive erfordert eine Situation, die solches Verhalten ethisch unbedenklich auslöst und geeignete messbare Parameter liefert. Der Open-Field Test als bekanntes Paradigma aus der Tierforschung erfüllt diese Voraussetzungen. Es war Ziel des Promotionsvorhabens, in einem realen Open-Field Test bei Agoraphobiepatien-ten und hochängstlichen Probanden Thigmotaxis als ethologisches Angstverhalten nachzuweisen und mit dem Verhalten einer Kontrollgruppe bzw. niedrigängstlichen Personen zu vergleichen (Studie I). Thigmotaxis ist eine Bewegungstendenz entlang des Randes und wird im Tiermodell als Index für Angst benutzt. Es sollte die Frage geklärt werden, ob agoraphobes Verhalten evolutionär verankert werden kann. Ziel von Studie II war die Untersuchung der Wege in einer typischen Alltagstopographie. Dazu wurden Unterschiede im Raum-Zeit-Verhalten von Agora-phobiepatienten vs. Kontrollgruppe, sowie hoch- vs. niedrigängstlichen Probanden beim Gehen durch die Stadt verglichen. Die Aufzeichnung des Raum-Zeit-Verhaltens erfolgte in beiden Studien per GPS-Tracking. Studie I zeigte an insgesamt 69 Studienteilnehmern, dass Angstverhalten mit ethologischer Bedeutung bei Menschen im Open-Field Test eindeutig messbar ist. Agoraphobiepatienten zeigten während der Exploration eines ungefährlichen freien Fußballfeldes deutlich mehr Thigmotaxis und Vermeidung der Mitte als die Kontrollgruppe. Hochängstliche im Vergleich zu niedrigängstlichen gesunden Probanden zeigten dies ebenfalls. So konnte die Vermutung unterstützt werden, dass die Agoraphobie möglicherweise eine evolutionäre Entsprechung in der tierischen Extraterritorialangst hat. Die Befunde sprechen auch für eine gemeinsame Prädisposition zu Sicherheitsverhalten bei pathologischer Angst und hoher Ängstlichkeit. Die Bedeutung gemeinsamer Verhaltensdispositionen bei klinischen und nicht-klinischen Gruppen kann im Hinblick auf gemeinsame Endophänotypen für die neuronale Angstverarbeitung diskutiert werden. Zuletzt konnte mit dem Open-Field Test ein aus der Tierforschung bekanntes ethoexperimentelles Paradigma auf den Menschen übertragen werden, was die Gültigkeit des Tiermodells unterstützt. Studie II lieferte Unterschiede in den Wegen der Agoraphobiepatienten vs. Kontrollpersonen bei der Passage des Marktplatzes. Die Patienten überquerten den Marktplatz seltener als die Kon-trollgruppe, und tangierten ihn häufiger am Rand. Die Daten konnten in korrelativen Zusammenhang mit der Vermeidung der Mitte im Open-Field Test gebracht werden. Dies deutet auf eine starke Auswirkung der agoraphoben Symptomatik auf das Raum-Zeit-Verhalten in unterschiedlichen Situationen hin. Im Weiteren zeigte Studie II, dass sich GPS Tracking als Assessment-Methode in der klinischen Psychologie eignet. Bei den hoch-und niedrigängstlichen Probanden fand sich bei der Passage des Marktplatzes kein Unterschied, aber der weitere Streckenverlauf lieferte Hinweise darauf, dass bei hoher Ängstlichkeit die Navigation entlang häufig zurückgelegter Strecken bevorzugt werden könnte. Schlussfolgerung des explorativen Vorgehens bei Studie II ist, dass es sich lohnt, den Zusammenhang zwischen Emotion und Navigation in komplexer Umgebung weiter zu untersuchen / Anxiety behavior in panic disorder and agoraphobia patients usually is treated as “safety seeking”. For optimal therapy outcome, these behaviors should be completely reduced. This is discussed controversial in scientific research. Little is known about the ethological meaning of such behaviors. This is surprising precisely because panic disorder and agoraphobia often is seen as intensification of extraterritorial fear known from animal research. In rodent models of anxiety numerous ethoexperimantal paradigms are known to study anxiety behavior. The crucial point in deriving answers from animal models of anxiety is that this is done unless studying humans directly is not practical. An ethoexperimental approach to study unconditioned anxiety behavior in men requires a situation to elicit these kind of behavior ethically uncritical and provides data for parametric analysis. The open-field test is a widely accepted paradigm in animal research that seems to meet these criteria. The aim of the dissertation was to verify thigmotaxis as anxiety like behavior under ethological perspective in a real world open-field test for agoraphobic patients vs. healthy controls and high- vs. low anxiety-sensitive persons. Thigmotaxis known as wall-hugging is used as index for anxiety in animal research (study I). A further aim was to search for differences in spatio-temporal behavior of agoraphobics vs. healthy controls and high- vs. low anxiety persons during a pedestrian walk through a complex and naturalistic environment (study II). Spatio-temporal-behavior was tracked per global positioning system (GPS). In study I and II 69 subjects participated. In study I it could be clearly demonstrated, that humans in a real open-field Test showed etho-logically based anxiety like behavior. Thigmotaxis automatically was activated in agoraphobic patients and high anxiety participants during the free exploration of a non-dangerous football field. This was considerably less in healthy controls and low-anxiety persons. These findings point to a shared predisposition in pathological and high trait anxiety for prepotent ethological anxiety behavior in extraterritorial situations. The meaning of such shared behavior traits can be discussed in respect of endophenotyping neurobiological mechanisms for anxiety disorders. Moreover the open-field test as eminent procedure for tests of emotionality in animals could be transferred to human subjects in the present study. In study II differences could be revealed in spatio-temporal-behavior of agoraphobic patients and healthy controls in the way they crossed the marketplace. Agoraphobics in most cases did not cross the marketplace directly, instead they passed it on a sideway. Variations in crossing or not crossing the marketplace well correspond with thigmotaxis in the previous open-field-test. This shows a strong impact of agoraphobic disorder on spatio-temporal-behavior in different situations. Moreover study II clearly demonstrates the practicability of GPS-technology in psychological research. In high- and low-anxiety participants there no difference in passing the marketplace was could be revealed. Unexpectedly a difference in subsequent segments on the return trip on foot was indicated. High anxiety participants seemed to stronger orient themselves towards well-worn routes, while low anxious participants walked straightforward towards the specified destination. This exploratory approach implicates to future research on the interaction of emotion and navigation.

Integration of GPS with Inertial Navigation Systems (INS) can provide reliable and complete positioning and geo-referencing parameters including position, velocity and attitude for dynamic platforms for a variety of applications. This research has been focusing on four modelling and implementation issues for a GPS/INS integrated platform in order to improve the overall integration performance, in particular: a) Time synchronization Having recognised that having a precise time synchronisation of measurements is fundamental in constructing a multi-sensor integration platform and is critical for achieving high data fusion performance, various time synchronisation scenarios and solutions have been investigated. A criterion for evaluating synchronisation accuracy and error impacts has been derived; an innovative time synchronisation solution has been proposed; an applicable data logging system has been implemented with off-the-shelf components and tested. b) Noise suppression of INS raw measurements Low cost INS sensors, especially MEMS INS, would normally exhibit much larger measurement noise than conventional INS sensors. A novel method of using vehicle dynamic information for de-noising raw INS sensor measurements has been proposed in this research. Since the vehicle dynamic model has the characteristic of a low pass filter, passing the raw INS sensor measurements through it effectively reduces the high frequency noise component. c) Adaptive Kalman filtering The present data fusion algorithms, which are mostly based on the Kalman filter, have the stringent requirement on precise a priori knowledge of the system model and noise properties. This research has investigated the utilization issues of online stochastic modelling algorithm, and then proposed a new adaptive process noise scaling algorithm which has shown remarkable capability in autonomously tuning the process noise covariance estimates to the optimal magnitude. d) Integration of a low cost INS sensor with a standalone GPS receiver To improve the performance where a standalone GPS receiver integrated with a MEMS INS, additional velocity aiding and a new integration structure has been adopted in this research. Field test shows that velocity determination accuracy could reach the centimetre level, and the errors of MEMS INS have been limited to such a level that it can generate stable attitude and heading references under low dynamic conditions.

<p>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.</p><p>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.</p><p>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.</p><p>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.</p>

<p>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.</p>

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