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Based on the targets outlined by the EU Horizon 2020 (H2020) framework, it is expected that heterogeneous networking will play a crucial role in delivering seamless end-to-end ubiquitous Internet access for users. In due course, the current GSM-Railway (GSM-R) will be deemed unsustainable, as the demand for packet-oriented services continues to increase. Therefore, the opportunity to identify a plausible replacement system conducted in this research study is timely and appropriate. In this research study, a hybrid satellite and terrestrial network for enabling ubiquitous Internet access in a high-speed train environment is investigated. The study focuses on the mobility management aspect of the system, primarily related to the handover management. A proposed handover strategy, employing the RACE II MONET and ITU-T Q.65 design methodology, will be addressed. This includes identifying the functional model (FM) which is then mapped to the functional architecture (FUA), based on the Q.1711 IMT-2000 FM. In addition, the signalling protocols, information flows and message format based on the adopted design methodology will also be specified. The approach is then simulated in OPNET and the findings are then presented and discussed. The opportunity of exploring the prospect of employing neural networks (NN) for handover is also undertaken. This study focuses specifically on the use of pattern classification neural networks to aid in the handover process, which is then simulated in MATLAB. The simulation outcomes demonstrated the effectiveness and appropriateness of the NN algorithm and the competence of the algorithm in facilitating the handover process.

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The Tracking and Data Relay Satellite System (TDRSS) Multiple Access (MA) Return Service provides a communication path that originates at a customer platform (either a spacecraft or other type of emitter) and is routed through a geosynchronous Tracking and Data Relay Satellite (TDRS) back to a customer control center or data acquisition location. Conventional operations provide Space Network (SN) customers with MA Service based on a schedule generated from user requests. The MA Service currently provides return link telemetry services to customer platforms with real-time, playback, and science data rates up to 100 kbps. This paper describes an integrated approach, using state-of-the-art technology and fault-tolerant architecture, to develop the next generation of TDRSS MA beamforming equipment. New designs will result in significant reduction in beamformer size and cost by at least an order of magnitude relative to the current MA equipment. This new equipment will provide the potential for increased usage of TDRSS MA services. The paper describes the in-development Demand Access (DA) Return Service that provides a new class of service using next generation technology.

Les technologies mobiles terrestre et satellite sont naturellement complémentaires. Les réseaux cellulaires terrestres sont adaptés aux villes où la densité d'utilisateurs est maximale mais perdent leur rentabilité dans les zones peu peuplées. A l'inverse, les systèmes mobile satellite permettent de couvrir de vastes zones à moindre coût mais n'assurent pas la couverture dans les zones urbaines car le signal est bloqué par les constructions. En les combinant pour assurer la couverture en ville par le réseau terrestre et dans les zones moins denses avec le satellite, on obtient un système à la couverture totale pour un coût optimal. Nous appelons un tel système intégrant une composante satellite et une composante terrestres un "système intégré" satellite/terrestre. Nul doute que d'ici quelques années, le rêve de la communauté satellite de rendre tous les terminaux mobiles capables de se connecter à un satellite sera accessible. Le satellite pourra ainsi être vu par les utilisateurs de terminaux portables comme une énième technologie d'accès à un système "intégré", aux côtés du Bluetooth, du Wifi et des technologies cellulaires (GSM, UMTS, LTE). La réutilisation du spectre satellite par les systèmes terrestres est un facteur déterminant dans le succès de cette intégration car elle permet de justifier les investissements dans le système satellite qui ne peut être rentabilisé par les abonnements seuls. Toutefois sa mise en œuvre pose de nombreux problèmes : règlementaires, commerciaux et bien entendu techniques. Cette thèse apporte des solutions sur ce dernier point et j'espère qu'elle contribuera ainsi à rendre possible ce rêve d'intégration. Nous avons adopté une approche descendante du problème du partage de spectre dans les systèmes mobiles satellite-terrestre. Nous avons tout d'abord établi une synthèse sur les aspects recouverts par l'intégration des systèmes mobiles satellite et terrestre. Nous avons ensuite dressé l'état de l'art sur la problématique de la réutilisation du spectre satellite par les systèmes terrestres, que nous avons complété par nos analyses. Nous avons décidé dans cette thèse de nous focaliser sur un des problèmes majeurs soulevés par cette réutilisation : les interférences co-fréquence du système terrestre sur le lien montant satellite. A partir de l'analyse d'une solution de partage statique de spectre par coordination des plans de fréquence (principe de zone d'exclusion), nous avons élaboré puis analysé les performances de mécanismes innovants d'allocation de ressources dans le système terrestre qui permettent de réduire de façon importante les interférences. De plus, nous proposons une méthode pour garantir au système satellite que les interférences subies sur son lien montant soient inférieures à une valeur limite. Enfin, nous définissons une architecture et les mécanismes associés qui permettent l'implantation des solutions proposées dans un système satellite-terrestre fondé sur la technologie LTE. L'étude du sujet de partage de spectre dans les systèmes mobiles satellite-terrestre est relativement nouvelle et cette thèse constitue donc un travail novateur important qui pourra être utilisé comme base à de futurs travaux. / Terrestrial and satellite mobile technologies are naturally complementary. Terrestrial cellular systems are adapted to urban areas where the user density is maximal but their cost-effectiveness is much lower in sparsely populated areas. On the contrary, mobile satellite systems cover large zones at a relatively low cost but they cannot ensure coverage in urban areas because of signal blockage due to buildings. By combining both systems for ensuring coverage in cities with terrestrial networks and in less dense areas with the satellite, we obtain a system with complete coverage for an optimal cost. Such a system is called mobile terrestrial and satellite "integrated system". It is likely that in a few years, the dream of enabling satellite connectivity on all mobile terminals will be within reach. The satellite will then be perceived for mobile terminal users as an additional access technology to an "integrated network" comparable to Wifi, Bluetooth or cellular technologies (GSM, UMTS, LTE). The spectrum reuse by terrestrial systems is a key for the success of this integration because it justifies part of the investments in the satellite systems that cannot be supported by user subscriptions only. However, implementation of spectrum sharing generates many issues: regulatory, commercial and obviously technical. This thesis brings answers on the latter and I hope it will contribute to make this dream of integration become reality. We used a descending approach of the issue of spectrum sharing in terrestrial and satellite mobile systems. First, we establish a synthesis of all the aspects covered by the integration of mobile satellite and terrestrial systems. Then, we made the state of the art on the issue of satellite spectrum reuse by terrestrial systems and we completed it with our analysis. We decided to focus our work on one of the major issues raised by this reuse: co-frequency interference generated by the terrestrial system on the satellite uplink. From the analysis of a solution proposing a static spectrum sharing by coordination of frequency plans (the exclusion zone principle), we elaborated and analyzed performances of innovative mechanisms of resources allocation in the terrestrial system that allows to reduce significantly the interferences. Moreover, we proposed a method for guaranteeing to the satellite system that interferences from the terrestrial system will not exceed a given threshold. At last, we define an architecture and the associated mechanism that allow the implementation of our solution in an integrated terrestrial-satellite systems based on LTE technology. The study of spectrum sharing in terrestrial-satellite mobile systems is rather new and this thesis represents an innovative work that may serve as a basis for future studies on this issue.

Localisation, which is a mechanism for discovering the spatial relationship between objects, is an area that has received considerable research and development in recent times. A common name given to localisation operations based on the absolute reference frame of Earth is Geolocation. One important example of geolocation research is E-911, where wireless carriers in the United States must provide the location of 911 callers. The operation of E-911 can be based on either a network configuration, or the Global Positioning System (GPS). With the importance of localisation being acknowledged, a review concerning the vulnerability of the Global Navigation Satellite System (GNSS) is provided as background and motivation for this research. With the current vulnerability of GNSS, this dissertation presents the results of a research program undertaken with the objective of developing an electromagnetic localisation technique that can determine the relative position of GPS Radio Frequency Interference (RFI) sources. Intended for operation in a hostile environment, blind and passive localisation methodologies must be incorporated into the developed model. In performing localisation research, a background of current techniques is provided in addition to a review of current electromagnetic propagation models. From the review of propagation models, the Parabolic Equation Model (PEM) was chosen for investigation concerning localisation. The selection of PEM is due to model properties that are required for blind/passive localisation. The localisation system developed in this research program is based on the integration of inverse diffraction propagation (IDP) within the parabolic equation model. The title chosen for the localisation method is Inverse Diffraction Parabolic Equation Localisation System (IDPELS). This thesis presents the simulation and field trial results of IDPELS. Under simulation, the terrain or obstacle profiles were not based on any geodetic datum. Any estimate provided by IDPELS under simulation is therefore a "Localisation" solution. In the field trials however, IDPELS operation is referred to as "Geolocation" as geodetic datum's where used to determine the receiver's position. Under simulation analysis, IDPELS operation was considered to provide good promise as it could simultaneously perform localisation on multiple transmission sources. In each investigated simulation scenario, a display of signals amplitude (dB units) is displayed over the entire region. By determining the field convergence regions, a localisation estimate of IDPELS is provided. By defining the convergence regions as areas having the greatest signal amplitude values (i.e. ≥ 99%), elliptical areas as low as 3.2m² were considered to indicate an excellent localisation capability. With the theoretical validity of IDPELS operation in electromagnetics having been established under simulation, further investigation into the practical feasibility of the IDPELS was performed. The field trials positioned a continuous-wave (CW) transmission source at a known location. By measuring signal phasors along a straight section of road, the geodetic spatial-phase profile was used as the input signal for IDPELS. Road sections used were cross-wise to the transmitter's boresight. Many data sets were recorded, each being made over a sixty second time period. Different regions and ranges where used to continuously measure the spatial-phase profile of the signal with fixed antennas in a moving vehicle. Such a measurement process introduced an analogy with Synthetic Aperture Radar (SAR) processes. In quantitating the accuracy of the IDPELS geolocation estimate in field trials, the linear error of range and cross-range components was analysed. A free-space PEM model was chosen for development of IDPELS and hence, data sets demonstrating properties of a free-space environment were able to be considered suitable for testing of the geolocation method. Data sets demonstrating free-space propagation characteristics were measured at the base of the Mt Lofty ranges in South Australia, where the range and cross-range error are respectively 3.14m, and 0.15m. Such low error values clearly demonstrate the practical feasibility of IDPELS geolocation. With the practical feasibility of IDPELS having been established in this research program, a novel contribution to electromagnetic geolocation methodologies is provided. An important characteristic of any geolocation technique concerns its robustness to operate in a wide variety of possible environments. With continued development of IDPELS, the robustness of this passive/blind geolocation technique can be enhanced. Further assistance with geolocation of multiple transmission sources is also indicated to be available by IDPELS, as shown in the simulation analysis.

The construction of fish passes has been a longstanding measure to improve river ecosystem status by ensuring the passability of weirs, dams and other in- channel structures for migratory fish. Many fish passes have a low biological effectiveness because of unsuitable hydrodynamic conditions hindering fish to rapidly detect the pass entrance. There has been a need for techniques to quantify the hydrodynamics surrounding fish pass entrances in order to identify those passes that require enhancement and to improve the design of new passes. This PhD thesis presents the development of a methodology for the rapid, spatially continuous quantification of near-pass hydrodynamics in the field. The methodology involves moving-vessel Acoustic Doppler Current Profiler (ADCP) measurements in order to quantify the 3-dimensional water velocity distribution around fish pass entrances. The approach presented in this thesis is novel because it integrates a set of techniques to make ADCP data robust against errors associated with the environmental conditions near engineered in-channel structures. These techniques provide solutions to (i) ADCP compass errors from magnetic interference, (ii) bias in water velocity data caused by spatial flow heterogeneity, (iii) the accurate ADCP positioning in locales with constrained line of sight to navigation satellites, and (iv) the accurate and cost-effective sensor deployment following pre-defined sampling strategies. The effectiveness and transferability of the methodology were evaluated at three fish pass sites covering conditions of low, medium and high discharge. The methodology outputs enabled a detailed quantitative characterisation of the fish pass attraction flow and its interaction with other hydrodynamic features. The outputs are suitable to formulate novel indicators of hydrodynamic fish pass attractiveness and they revealed the need to refine traditional fish pass design guidelines.

The master thesis The usage of Global Navigation Satellite Systems in the transnational transport of dangerous goods examines the possibilities of space-based radio-navigation systems in the transport sector, specifically in the carriage of hazardous materials. The author puts an emphasis on identifying the economic and other benefits, as well as the downsides from the key users perspective, which is accomplished by means of interaction with said stakeholders. The dissertations final part aims to point to the factors decisive in the future development with regard to societal needs on both national and European Union levels.

The subject of this thesis is to assessment of the accuracy of town plans. The analytical work are transferred to available historical cartographic works with Senica and surrounding area. In the theoretical part of the work deals with describing the documents. Furthermore, it describes methods of measurement. The practical part deals with how to detect positional deviations from the selected database points.

Global Navigation Satellite System/Inertial Measurement Unit (GNSS/IMU) Integrated Navigation Systems (INS) integrate the positive features of GNSS and IMU for optimal navigation guidance in high accuracy outdoor navigation systems, for example using Extended Kalman Filter (EKF) techniques. Time synchronization of IMU data with precise GNSS based time is necessary to accurately synchronize the two systems. This must be done in real-time for time sensitive navigation applications such as autonomous vehicles. The research is done in two parts. The first part is the simulation of inaccurate time-stamping in a single axis of nonlinear input data in a gyroscope and an accelerometer, to obtain the timing error value that is tolerable by a high accuracy GNSS/INS system. The second part is the creation of a real-time algorithm using an STM32 embedded system enabled with FreeRTOS real-time kernel for a GNSS receiver and antenna, along with an IMU sensor. A comparative analysis of the time synchronized system and an unsynchronized system is done based on the errors produced using gyroscope and accelerometer readings along a single axis from the IMU sensor, by conducting static and rotational tests on a revolving chair.The simulation concludes that a high accuracy GNSS/INS system can tolerate a timing error of up to 1 millisecond. The real-time solution provides IMU data paired with updated GNSS based time-stamps every 5 milliseconds. The timing jitter is reduced to a range of ±1 millisecond. Analysis of final angular rotation error and final position error from gyroscope and accelerometer readings respectively, indicate that the real-time algorithm produces a reduction in errors when the system is static, but there is no statistical evidence showing the reduction of errors from the results of the rotational tests. / GNSS / IMU integrerade navigationssystem kombinerar de positiva egenskaperna hos GNSS och IMU för optimal prestanda i noggranna navigationssystem. Detta görs med hjälp av sensorfusion, till exempel EKF. Tidssynkronisering av IMU-data med exakt GNSS-baserad tid är nödvändigt för att noggrant synkronisera de två systemen. Detta måste göras i realtid för tidskänsliga navigationsapplikationer såsom autonoma fordon. Forskningen görs i två delar. Den första delen är simulering av icke-linjär rörelse i en axel med felaktig tidsstämpling hos ett gyroskop och en accelerometer. Detta görs för att erhålla det högsta tidsfel som är acceptabelt hos ett GNSS / INS-system med hög noggrannhet. Den andra delen är skapandet av en realtidsalgoritm med ett inbyggt STM32-system med FreeRTOS som realtidskärna för en GNSSmottagare och antenn, tillsammans med en IMU-sensor. En jämförande analys av det tidssynkroniserade systemet mot ett osynkroniserat system görs baserat på de positionsfel längs en axel som produceras av gyroskopoch accelerometermätningar. Detta görs genom att utföra statiska och roterande tester med hjälp av en roterande stol.Simuleringen visar att ett noggrant GNSS / INS-system tolererar ett tidsfel på upp till 1 millisekund. Realtidslösningen ger IMU-data med tidsstämplar synkroniserade med GNSS-tid var femte millisekund. Tidsjittret reduceras till ett intervall mellan ± 1 millisekund. Analysen av det slutliga vinkelrotationsfelet och positionsfelet från gyroskopoch accelerometermätningar indikerar att realtidsalgoritmen ger ett lägre fel när systemet är statiskt. Det finns dock inga statistiska bevis för förbättringen från resultaten av rotationstesterna.

Vid GNSS-positionering i samband med fastighetsbildningsåtgärder används vanligtvis den traditionella RTK-mätningen (Real-Time Kinematic) via SWEPOS nätverks-RTK-tjänst. Denna tjänst kräver mobiltelefontäckning eller motsvarande tvåvägskommunikation, vilket kan vara problematiskt inom områden med bristfällig mobiltelefontäckning. Under dessa förhållanden kan istället PPP-mätning (Precise Point Positioning) vara användbart vid fastighetsbildningsåtgärder då dessa tjänster tar emot korrektionsdata i realtid från satelliter. PPP kräver inte någon mobiltelefontäckning, däremot krävs en kommunikationslänk, en RTX-tjänst för att erhålla korrektioner externt från en RTX-satellit. Syftet med studien är att undersöka möjligheten till att nyttja PPP i realtid vid fastighetsbildningsåtgärder som ett alternativ till traditionell GNSS-mätning med nätverks-RTK. För att PPP ska vara ett alternativ till traditionell GNSS-mätning i realtid krävs det att mätosäkerhetskraven inom fastighetsbildning uppfylls. Mätosäkerheten undersöktes genom att utgå ifrån redan kända koordinater (RIX 95-punkter). Mätningarna har genomförts på fem olika platser i Sverige, Göteborg, Vänersborg, Karlstad, Torsby och Malung-Sälen. Mätdata som erhölls från undersökningsplatserna har analyserats samt jämförts med fastighetsbildningskraven. Resultatet av studien erhölls i form av analyserad mätdata med jämförelser mot redan kända (RIX 95) punkter. Avikelsen från känd RIX 95-punkt redovisas i resultatet utifrån tidsaspekten, den systematiska avvikelsen av translativ art, förändringar i avvikelsen från söder till norr samt utifrån två beräkningsmodeller, varav en translation och en transformation. För att få den erhållna mätdatan från RTX-tjänsten att överensstämma bättre med referenspunkten (RIX 95-punkten) togs beräkningsmodellerna fram för att möjliggöra modellering av systematiska avvikelser som uppkommit och därmed uppfylla kraven inom fasighetsbildningsåtgärder. Genom att ha analyserat och granskat olika samband har det framkommit att efter ca 20 minuters mätning, börjar precisionen för mätningarna att bli stabila. Utifrån resultatet är slutsatsen att PPP inte fungerar vid fastighetsbildningsåtgärder för områden inom stomnät, däremot fungerar metoden för skogs- och jordbruksfastigheter utanför stomnät. Förutsatt att en modellering genom translation alternativt transformation som är framtagen i denna studie används för att justera koordinaterna så fungerar PPP-mätning inom samtliga fastighetsbildningsåtgärder. Detta kräver då att mätdata erhålls efter 20 minuters mätning eller mer. / GNSS positioning in conjunction with the real property is usually used the traditional RTK measuring (Real-Time Kinematic) by SWEPOS network RTK service. This service requires mobile phone coverage or equivalent two-way communication, which can be problematic in areas with poor mobile phone coverage. Under these circumstances, PPP (Point Positioning Precise) could be more useful in real property measures when such services receives the correction data in real time from the satellites. PPP does not require any cell phone coverage, however it requires a communication link, a RTX service to obtain corrections externally from a RTX satellite. The purpose of the study is to examine the possibility of using PPP in real time at the real property as an alternative to traditional GNSS measurements with network RTK. The measurement uncertainty was investigated by starting out from already known coordinates (RIX 95 points). The measurements were performed out at five different locations in Sweden, Gothenburg, Vanersborg, Karlstad, Torsby and Malung-Salen. Measurement data obtained from the observations have been analyzed and compared with real property requirements. The results of the study were obtained in the form of data analyzed by comparison of the known (RIX 95) points. The deviation is known from RIX 95 point recognized in income based on the time factor, the bias of the translative case species, changes in deviation from south to north and from two calculation models, a translation and a transformation. To correct the measured values from the RTX service for a better match to the RIX 95 points calculation models were developed to facilitate the modeling of systematic deviations incurred and meet the demands of real property. Analyzing and examining various relationships have shown that after about 20 minutes of measuring, the precision of the measurements starts to become more stable. Based on the results, the conclusion is that the PPP does not work in real property areas within the core network, however, the method works for forestry and agricultural properties outside the core network. Assuming a modelling through translational alternative transformation, developed in this study is used to adjust the coordinates, the PPP measurement is working in all real property registration measures. This requires that the measurement data is obtained after 20 minutes of measurement or more.