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The objective is to use artifitial intellegence techniques with satellite images for predicting the forest fires severity., Aquest projecte presenta l'anàlisi de l'efecte de diferents paràmetres geofísics als episodis de dengue i la propagació de grans incendis a Indonèsia. Els satèl·lits d'observació de la terra permeten monitoritzar de manera regular i amb resolucions espacials cada cop millors paràmetres geofísics a nivell global. La monitorització d'aquests paràmetres permet desenvolupar noves aplicacions que poden ser útils per predir el risc de produir-se desastres naturals com ara incendis, inundacions i la propagació d'algunes epidèmies. El ministeri de salut d'Indonèsia va proporcionar el nombre de casos de dengue anuals que ha permès fer una anàlisi de correlacions dels diferents paràmetres. Les dades mensuals no van arribar a temps per poder desenvolupar un algorisme de predicció de risc d'epidèmia del dengue. D'altra banda, s'ha desenvolupat un algorisme de predicció d'àrea potencial cremada a la zona del sur de Kalimantan, a Indonèsia. S'ha aplicat un algorisme de Machine Learning i s'han utilitzat dades registrades d'incendis en aquesta zona durant el període del 2010 al 2020, Este proyecto presenta el análisis del efecto de distintos parámetros geofísicos en los episodios de dengue y la propagación de grandes incendios en Indonesia. Los satélites de observación de la tierra permiten monitorizar de forma regular y con resoluciones espaciales cada vez mejores parámetros geofísicos a nivel global. La monitorización de estos parámetros permite desarrollar nuevas aplicaciones que pueden resultar útiles para predecir el riesgo de producirse desastres naturales como incendios, inundaciones y la propagación de algunas epidemias. El ministerio de salud de Indonesia proporcionó el número de casos de dengue anuales que ha permitido realizar un análisis de correlaciones de los distintos parámetros. Los datos mensuales, no llegaron a tiempo para poder desarrollar un algoritmo de predicción de riesgo de epidemia del dengue. Por otro lado, se ha desarrollado un algoritmo de predicción de área potencial quemada en la zona del sur de Kalimantan, en Indonesia. Se ha aplicado un algoritmo de Machine Learning y se han utilizado datos registrados de incendios en esta zona en el periodo de 2010 a 2020.

Low Earth Orbit satellite communications nowadays are an increasingly popular method to provide coverage and Internet access globally. Worldwide companies such as SpaceX (via Starlink) or ViaSat are launching full constellations of LEO nanosatellites to ensure correct coverage levels all around the globe. The aim of this work is to study the benefits of array processing and beamforming, especially for downlink satellite communications, in order to provide proper received power to the serving user while keeping interferences to other nearby users as low as possible. This scenario is particularly significant when considering densely user-populated deployments or, in general, in situations where multiple end users are located in the same satellite footprint area.

In recent timeps, SLR (Satellite Laser Ranging) is being used lately for orbit determination in many satellite constellations. It improves the accuracy of traditional radiofrequency systems by using laser transmitters, but the short-wavelength signals that are used in the lasers make them very weak against the atmospheric effects between the ground station and the satellite. In this thesis, the study on how the clouds affect the contact plan of the SLR stations will be done. For this, LEO, MEO and GEO constellations will be considered, as well as three ground station scenarios: cloudless, cloudy and hybrid. The contact plan for each ground station scenario with each satellite constellation will be executed to analyze the results, and draw conclusions.

Having the capability to acquire insightful knowledge about the spatial environment is crucial and pressing for States, as it is closely linked to sovereignty, security and intelligence issues. One important aspect of it is to be able to detect when a foreign orbiting object operates a maneuver. This thesis aims at comparing the use of TLE, a common but imprecise satellite trajectory data type to SP vectors, a rare but more precised trajectory data type, in the context of satellite maneuver detection. We first introduce key concepts of spatial kinematics and explore both TLE and SP data to deduce adequate features for maneuver detection. Then, three outlier detection algorithms are introduced, Gaussian Mixture Model, Local Outlier Factor and Isolation Forest. These algorithms are tested on both TLE and SP data. Finally the results show that SP based detection methods seem, in average, to surpass the performances of TLE based detection methods., Outgoing

Nowadays, Internet access is becoming a valued and essential asset to ensure the economic development, growth and profit of any human being, company or institution. For years now, the most developed regions of the world have been investing large amounts of private and public resources into the deployment of telecommunications networks to guarantee access to this service. Nevertheless, such deployment has gradually led to a territorial inequality of access to the Internet. In addition, the outbreak of the COVID-19 global pandemic has brought notable changes in society in terms of lifestyle and consumption habits. All these changes have led to certain new necessities in society, including the majority of current telecommunication services in areas where the demand or necessity for connection was minimal or non-existent. It is precisely for this reason that the outlying territories and rural areas have now become the areas with the greatest demand for the deployment of a technological model that guarantees a reliable and high-quality broadband Internet service. As a result of this requirement, the project focuses on the study and analysis of the main features of all the technological models that currently offer broadband Internet services. One of the most innovative technological models is that of telecommunications via satellites in Very Low orbits; to understand such a technological system, an analysis of the business model developed by the leading company in this market, Starlink, has been carried out. Finally, in order to determine which of these systems is the most viable for all the territories that currently lack this type of service, besides considering the connection characteristics, a comparison of risks and environmental impacts has been carried out. After this investigation and research work, it has been concluded that the system of Internet access via satellites in the lowest area is the most suitable model to generate worldwide coverage; however, the irre, Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura, Objectius de Desenvolupament Sostenible::10 - Reducció de les Desigualtats

An effective and efficient characterization of the vegetation is key to being able to determine the appropriate amount of phytosanitary product to be applied when carrying out phytosanitary treatments in the vineyard. Vegetation evolves and develops based on factors linked to the soil, the climate or the physiology of the plant itself, and that is why within the same plot there is a certain spatial variability in crop growth. It has been proven that expressing the application volumes based on parameters linked to the crop, such as the leaf volume per surface unit, provide significant savings and improvements in the quality of the applications. These new methods of dose expression are based on manual measurements in the field, which are costly to carry out and sometimes slow down the introduction of these methodologies. New technologies such as remote sensing provide information at a global level and local resolutions, together with a high frequency of data. It is for this reason that an opportunity opens up to automate data acquisition processes, which in the case of the application of phytosanitary products involves being able to estimate the characteristics of the crop automatically. The aim of this project was to improve an existing mathematical model that allows to relate vegetation indices calculated from satellite images with vegetation measurements in different vegetative stages in vineyard cultivation. The existing model includes data from the years 2018 and 2019 and has a single vegetation index as an independent variable. During this project, the model was complemented with data acquired during the years 2021 and 2022, and 7 new spectral indices were calculated that served to develop new prediction models. The results showed that the existing model based on the Normalized Differential Vegetation Index (NDVI) and used to estimate the width of the vegetation, lost its predictive capacity when adding samples from 2021 and 2022. Similarly, the Normalized Red E, Una caracterització eficaç i eficient de la vegetació és clau per poder determinar la quantitat adequada de producte fitosanitari que cal aplicar quan es realitzen tractaments fitosanitaris a la vinya. La vegetació evoluciona i es desenvolupa en funció de factors lligats al sòl, al clima o a la mateixa fisiologia de la planta, i és per això que dins una mateixa parcel·la hi ha una certa variabilitat espacial en el creixement del cultiu. Ha quedat provat que expressar els volums d'aplicació en funció de paràmetres lligats al cultiu, com ara el volum de fulla per unitat de superfície, proporcionen importants estalvis i millores en la qualitat de les aplicacions. Aquests nous mètodes d¿expressió de dosis es basen en mesures manuals en camp, costoses de realitzar i que de vegades frenen la introducció d¿aquestes metodologies. Les noves tecnologies com la teledetecció aporten informació a nivell global i resolucions locals, juntament amb una alta freqüència de dades. És per aquest motiu que s'obre una oportunitat per automatitzar processos d'adquisició de dades, que en el cas de l'aplicació de fitosanitaris passa per poder estimar automàticament les característiques del cultiu. En aquest projecte es pretenia millorar un model matemàtic ja existent que permet relacionar índexs de vegetació calculats a partir d'imatge satèl·lit amb mesures de vegetació en diferents estadis vegetatius al cultiu de la vinya. El model existent comprèn dades dels anys 2018 i 2019 i compta amb un sol índex de vegetació com a variable independent. Durant aquest projecte es va complementar el model amb dades adquirides durant els anys 2021 i 2022, i es van calcular 7 nous índexs espectrals que van servir per desenvolupar nous models de predicció. Els resultats van mostrar que el model existent basat en el Normalized Differential Vegetation Index (NDVI) i que servia per estimar l'amplada de la vegetació, va perdre la capacitat predictiva en afegir mostres de 2021 i 2022. De la mateixa manera, l'ín, Una caracterización eficaz y eficiente de la vegetación es clave para poder determinar la cantidad adecuada de producto fitosanitario que debe aplicarse cuando se realizan tratamientos fitosanitarios en viñedo. La vegetación evoluciona y se desarrolla en función de factores ligados al suelo, al clima o a la misma fisiología de la planta, y es por eso que dentro de una misma parcela existe cierta variabilidad espacial en el crecimiento del cultivo. Ha quedado probado que expresar los volúmenes de aplicación en función de parámetros ligados al cultivo, como pueden ser el volumen de hoja por unidad de superficie, proporcionan importantes ahorros y mejoras en la calidad de las aplicaciones. Estos nuevos métodos de expresión de dosis se basan en medidas manuales en campo, costosas de realizar y que a veces frenan la introducción de estas metodologías. Las nuevas tecnologías como la teledetección, aportan información a nivel global y resoluciones locales, junto con una alta frecuencia de datos. Es por este motivo que se abre una oportunidad para automatizar procesos de adquisición de datos, que en el caso de la aplicación de fitosanitarios pasa por poder estimar las características del cultivo de forma automática. En este proyecto se pretendía mejorar un modelo matemático ya existente que permite relacionar índices de vegetación calculados a partir de imagen satélite con medidas de vegetación en distintos estadios vegetativos en el cultivo del viñedo. El modelo existente comprende datos de los años 2018 y 2019 y cuenta con un solo índice de vegetación como variable independiente. Durante este proyecto se complementó el modelo con datos adquiridos durante los años 2021 y 2022, y se calcularon 7 nuevos índices espectrales que sirvieron para desarrollar nuevos modelos de predicción. Los resultados mostraron que el modelo existente basado en el Normalized Differential Vegetation Index (NDVI) y que servía para estimar la anchura de la vegetación, perdió su capacidad predictiva, Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables

Information about lightning activity and its parameters is necessary to design and evaluate the lightning protection of an electrical power system. This information can be obtained from ground-based lightning detection networks that provide information on cloud-to-ground lightning strikes with a location accuracy of few hundred meters. Recently, the first satellite-based lightning optical detectors are operating continuously from geostationary orbits. These imagers observe the luminosity escaping from clouds to detect and locate total lightning activity with a spatial accuracy of several kilometers. This allows delineating the initiation and propagation (sometimes over tens to hundreds of kilometers before striking the ground) not observable by the ground-based networks. In this paper, we explore the use of this new technology for lightning protection in power systems. We focus on tall objects such as wind turbines and overhead transmission lines. We show how the optical detections allow identifying lightning flashes that likely produce continuing currents. This provides additional information for the identification of dangerous events and also can be used to estimate the number of upward-flashes from tall objects triggered by a nearby flash. The analysis of a transmission line shows the concentration of faults in the areas of high total lightning flash density. We found regional variations of the optical energy of the flashes along the line., This work was supported by research grants ESP2017-86263-C4-2-R funded by MCIN/AEI/ 10.13039/501100011033 and by “ERDF A way of making Europe”, by the “European Union”; and Grants PID2019- 109269RB-C42 and ENE2017-91636-EXP funded by MCIN/AEI/ 10.13039/501100011033. S. Goodman was in part supported by NASA Grant 80NSSC18K1689. M. M. F. Saba was in part supported by research grants 2012/15375–7 and 2013/05784–0, from Sao ˜ Paulo Research Foundation (FAPESP). S. Visacro was supported by a research grant (307381/2019–6) of the Brazilian National Council of Technological and Scientific Development (CNPq). The GLM data are available from the NOAA National Centers for Environmental Information (NCEI) and Cloud Service Providers (e.g., Amazon Web Services, AWS). The LIS data are available from the NASA GHRC Distributed Active Archive Center (DAAC) (https:// https://ghrc.nsstc.nasa.gov/home/access-data. The power system information for the 500 kV transmission line is provided by ISA-INTERCOLOMBIA and is supported by L. Porras., Peer Reviewed, Postprint (author's final draft)

The objective of this work is the study and sizing of honeycomb panels, as a base/platform for flight equipment on board satellites. The specific structural design and calculation standards have been developed, which allow a viable implementation from the point of view of the necessary manufacturing and structural support. A detailed description of the mechanical characteristics, its limitations, its advantages and how it should be used for the mentioned purpose had been obtained. To carry out this work, CAD design (SIEMENS NX 12) and finite element calculation (MSC Patran/Nastran) programs had been used to define the design ranges and robust work of the panels. No prototype had been manufactured, but the results obtained would allow it to be done. All ESA and NASA regulations applicable to this type of element and materials had been used as a basis. Real-life project conditions to which these panels could be exposed during their useful life inside the satellite have been considered in simulations and analysis. In addition to developing the entire process of the design flow and the advantages in mass savings, results have been evaluated concerning the current solution. The whole project has been concluded from the bases of the current know-how and SENER Aeroespacial resources. This project has been developed throughout the duration of the internship agreement between SENER Aeroespacial, UPC and the student. Being completed by the end of the submission deadline. It must not only be a thesis but also support so that in the future it can be taken as a reference for the use of this material following the established indications. This information should be able to be added to the company's Know-how so that it can be used by the company.

[ES] La presente tesis doctoral tiene como objetivo principal el estudio, desarrollo, diseño y fabricación de nuevos componentes pasivos de microondas, tales como filtros y multiplexores que operen en las bandas de alta frecuencia de los actuales y futuros satélites de telecomunicación (bandas Ku, K y Ka) entre 12 y 40 GHz. Dichos componentes deben ser capaces de ofrecer tanto respuestas clásicas sencillas como avanzadas (elípticas), y presentar una capacidad de resintonización (tanto en términos de frecuencia central como de ancho de banda). Estos componentes darán solución a las necesidades actuales de los sistemas de comunicaciones espaciales, que requieren de mayores tasas de transmisión de datos (señales de mayor ancho de banda), así como de mayor flexibilidad en las frecuencias de operación, para ofrecer con un mismo dispositivo distintos servicios y prestaciones. Para ello, se proponen tanto modificaciones a las estructuras de filtros clásicos de microondas actuales, como la introducción de nuevas estructuras. Asimismo, también se investigará el uso de los tornillos de ajuste post-fabricación de los filtros como tornillos de sintonía metálicos, así como la posible introducción de tornillos de sintonía realizados con distintos materiales dieléctricos. Se pretende, de esta forma, mejorar las respuestas de los dispositivos actuales; reduciendo su tamaño y costes de producción (debido a la relajación de las tolerancias de fabricación), abaratando de esta forma la fabricación y futura operación de los mismos. Aprovechando estos nuevos dispositivos, se abordará también el diseño, fabricación y medida de componentes más complejos, como pueden ser los los diplexores de canal o los conmutadores con respuesta selectiva en frecuencia, todos ellos necesarios en los sistemas de comunicaciones espaciales y en íntima relación con los filtros previamente mencionados. Por último, el desarrollo de todos estos nuevos dispositivos vendrá acompañado de una metodología de diseño b, [CA] La present tesis doctoral té com a objectiu el estudi, desenvolupament, diseny i fabricació de nous components pasius de microones, tals com els filtres i multiplexors que operen en les bandes d'alta freqüencia dels actuals i futurs satèl.lits de telecomunicació (bandes Ku, K i Ka) entre 12 i 40 GHz, Aquests components han de ser capaços d'oferir tant, respostes clàsiques sencilles com avançades (eliptiques), i que a més a més presenten una capacitat de resintonització (tant en termes de freqüència central com d'amplada de banda). Aquestos nous components pasius donaràn solució a les necesitats dels actuals sistemes espacials, que requereixen de majors taxes de transmissió de dades (senyals de major amplada de banda), així com de major flexibilitat en les frequencies de operació, per oferir en un mateix dispositiu distints serveis i prestacions. Per aquesta raó, es proposen tant modificacions a les estructures del filtres clàsics de microones actuals, com la introducció de noves estructures. Així mateix, també s'investigarà l'us dels tornells d'ajustament post-fabricació dels filtres com a tornells de sintonía metàl.lica i la introducció de tornells de sintonía realitzats amb diferents materials dielèctrics Es pretén, d'aquesta forma, la millora de les respostes del dispositius actuals; reduint la envergadura i els costos de producció (gràcies a la relaxació de les toleràncies de fabricació), abaratint d'aquesta forma la fabricació i futura operació dels filtres mateixos. Aprofitant aquestos nous dispositius es treballarà també en el disseny, fabricaçió i mesura de components més complexes, com poden ser els multiplexors de canal i els commutadors amb resposta selectiva en freqüencia, tots ells necessaris en els sistemes de comunicacions espacials i en íntima relació amb els filtres abans esmenats. Per analitzar, el desenvolupament de tots aquestos dispositius vindrà acompanyat d'una metodologia de disseny basada en l'us del Mapatge Espacial Agressiu (Aggressiv, [EN] The main objective of this doctoral thesis is the study, development, design and manufacture of new passive microwave components in waveguide technology, such as filters and multiplexers, that operate in the high frequency bands of current and future telecommunication satellite payloads between 12 and 40 GHz (Ku, K and Ka bands). The new solutions developed must other both classic and advanced (elliptical) responses, as well as the possibility of being reconfigured both in terms of center frequency and bandwidth. The motivation for this research is to address the current and future needs of space communication systems which require higher data rate transmission (that is larger bandwidths), as well as flexibility with respect to the operating frequency to dynamic adaptation to possible changes in user demands. In this context, we propose in this thesis alternative microwave filter structures in metallic waveguide, as well as novel solutions. We explore different approaches to adjust the filter performance, using both traditional metallic tuning screws as well as tuning elements made with dierent dielectric materials. We also advance the state-of-the-art by developing more performing Space Mapping procedures for the design, optimization and tuning of the filter structures that we propose. The objective is to improve the response of the devices and reduce, at the same time, their manufacturing time and costs. As a fundamental element of our work, in addition to theoretical developments, we also apply the findings of our research to the design, manufacture and measurement of a number of more complex components, such as diplexers and integrated switches and filters. They are practical devices to demonstrate the ability of the novel filters that we propose to satisfy the requirements of current and future advanced satellite payloads.

Satellite soil moisture provides a wider range of spatial data than in-situ observations. Satellites are sensitive to measuring soil moisture in a few centimetres of the soil layer. However, root zone soil moisture is more important, especially in vegetated areas. Therefore, it is necessary to invert the near-surface soil moisture collected by satellite missions to estimate root zone soil moisture. This study quantified the association between near-surface and root zone soil moisture using in-situ data from the REMEDHUS network in Spain and Soil Moisture Ocean Salinity (SMOS) mission from 2014-2018, comparing SMOS with in-situ observations based on an exponential filter approach, optimizing an optimal characteristic time length (Topt) by computing the correlation coefficients (R) of the filtered satellite time series with in-situ time series. The results show that the exponential filter's main factor T is sensitive to soil moisture and varies depending on the climate. When using this method to infer root zone soil moisture, the eight stations' average R-value reached 0.71, meeting the "Strong correlation" standard. The root zone soil moisture obtained by SMOS surface inversion is compared with in situ soil moisture. The mean R-value of soil moisture in the root zone based on SMOS is 0.58, which is approximate to the "baseline error (0.6)" -- the accuracy of the surface soil moisture estimated by SMOS. However, attention should be paid to the effects of soil moisture season and soil texture on the experimental results.

Scintillation is a particular type of space weather disturbance that currently limits the accuracy and availability of the Global Navigation Satellite System. The present final master’s thesis aims to study the characteristics of satellite navigation techniques. First, evaluate the impact of scintillation on the frequencies and signals used in space-based navigation systems. For this, the TFM will make use of the Geodetic Detrending technique developed by research group Astronomy and Geomatics of the Universitat Politecnica de Catalunya (gAGE). The final objective of this TFM is to show that, once the scintillation effect has been detected, there are receptors that in combination with certain signals can influence navigation or the study of the atmosphere.

El Project Kuiper és la nova constel·lació de satèl·lits que serà desplegada per Amazon durant els propers anys i que estarà emplaçada a LEO amb l'objectiu principal de proporcionar connectivitat de banda ampla, d'alta velocitat i de baixa latència a les comunitats no ateses o mal ateses de totes les parts del món. Aquest projecte té com a objectius, primerament, estudiar aquesta nova constel·lació per tal de conèixer els beneficis que li aportarà la seva baixa òrbita terrestre i després, desenvolupar el seu model de negoci a través del Model de Negoci CANVAS per extreure els seus factos clau d'èxit. A més a més, també s'han estudiat les noves oportunitats de negoci que sorgiran gràcies al desplegament de constel·lacions d'aquestes característiques., Project Kuiper is the new constellation of satellites to be deployed by Amazon over the next few years and placed in LEO with the primary goal of providing high-speed, low-latency broadband connectivity to unserved and underserved communities around the world. This project aims firstly to study this new constellation in order to know the benefits that its low terrestrial orbit will bring and then to develop its business model through the Business Model CANVAS to extract its key success factors. In addition, the new business opportunities that will emerge from the deployment of constellations of these characteristics have also been studied.

Desde el comienzo de la era espacial, la filosofía de diseño de satélites estuvo dominada por diseños conservadores construidos con componentes altamente duraderos para soportar condiciones ambientales extremas. Durante las últimas dos décadas, la aparición de los CubeSats ha cambiado esta filosofía permitiendo todo un mundo de nuevas posibilidades. El despliegue de grandes constelaciones de CubeSats en órbita terrestre baja (LEO, en inglés) revolucionará el sector espacial al permitir ciclos de innovación más rápidos y económicos. Sin embargo, la confiabilidad de los CubeSats todavía se considera un obstáculo debido a las considerables tasas de fallo entre universidades y empresas, generalmente atribuidas a casos de pérdida completa de misión tras la eyección del desplegador orbital y al fallo de los subsistemas. Esta tesis se desarrolla en el marco del proyecto de investigación PLATHON, que pretende desarrollar una plataforma de emulación Hardware-in-the-loop para constelaciones de nanosatélites con comunicación óptica entre satélites y enlaces tierra-satélite. Un aspecto crucial de este proyecto es tener un propagador orbital suficientemente preciso con control de maniobras y representación gráfica en tiempo real. Los programas de propagadores disponibles se han analizado para seleccionar el sistema OpenSatKit de la NASA, una plataforma multifacética con un propagador incorporado conocido como 42. El propósito de esta disertación es analizar la viabilidad de implementación del programa para la creación de un banco de pruebas de constelaciones en comparación con un propagador previo desarrollado en MATLAB/Simulink. La documentación inicial es un enfoque de exploración para examinar las capacidades del 42 en distintos escenarios con objeto de adaptar el sistema PLATHON al funcionamiento interno y las limitaciones del programa. Las modificaciones y simulaciones del programa allanan el camino para el futuro desarrollo de la red interconectada PLATHON; específicamente, Since the beginning of the space age, satellite design philosophy was dominated by conservative designs built with highly reliable components to endure extreme environmental conditions. During the last two decades, the dawn of the CubeSats has changed this philosophy enabling a whole world of new possibilities. The deployment of monumental CubeSat constellations in low Earth orbit is set to revolutionise the space sector by enabling faster and economical innovation cycles. However, CubeSat reliability is still considered an obstacle due to the sizeable fail rates among universities and companies, generally attributed to the dead-on-arrival cases and subsystem malfunctions. This thesis is developed in the framework of the PLATHON research project that intends to develop a Hardware-in-the-loop emulation platform for nanosatellite constellations with optical inter-satellite communication and ground-to-satellite links. A crucial aspect of this project is to have a sufficiently precise orbital propagator with real-time manoeuvring control and graphical representation. The available propagator programmes are analysed to select NASA’s OpenSatKit, a multi-facet platform with an inbuilt propagator known as 42. The purpose of this dissertation is to analyse the implementation feasibility of the programme for the creation of a constellation testing bench compared to previously selfdeveloped propagators based on MATLAB/Simulink. The initial documentation is a scouting approach to examine 42’s capabilities under distinct scenarios to adapt the PLATHON system to the programme’s inner workings and constraints. The programme modifications and simulations pave the way for the future development of the interconnected PLATHON network; specifically, the inter-process communication capabilities have been tested to imitate the inputs of spacecraft attitude control systems through bidirectional socket interfaces.

La motivació d’escriure aquest informe sorgeix de la necessitat de comunicar els avions amb la Terra. Encara que pugui semblar que la tecnologia actual permet rastrejar els avions arreu del planeta, només és capaç de fer-ho en un 30% de la superfície. Gràcies a la infrastructura espacial de dispositius ADS-B, are és possible saber la situació i establir comunicació amb els avions sigui quina sigui la seva posició, ja estiguin al mig de l’oceà, sobrevolant regions polars o zones muntanyoses. En aquest informe es mostren les avantatges i aplicacions de l’Òribita Baixa Terrestre en relació al posicionament d’aeronaus així com el pla d’empresa d’una companyia oferint tal servei. Els resultats fruit d’un escenari economic neutre mostren un Retorn de la Inversió del 80% que suposen uns 150 milions de dòlars, uns valors més que prometedors. En definitiva, s’ha aconseguit un coneixement profund de la infrestructura tecnològica així com el desenvolupament dels processos de la cadena de valor d’una empresa espacial de dispositius ADS-B., The motivation of this report arises from the need to link aircraft to the Earth. Although it may seem that the current technology is able to track the airplanes wherever on the planet, they are only capable of doing so in a 30% of the Earth’s surface. Thanks to the space-based ADS-B infrastructure, it is now possible to provide surveillance and broadcast to aircraft no matter if they are in the middle of the ocean, flying over polar regions or in mountainous zones. This report shows the benefits and applications of the Low Earth Orbit regarding aircraft surveillance and a brand-new business plan of a company providing such service. The results in a neutral economic scenario show a Return of Investment of 80% and translated to money that is $ 150M, more than promising values. All in all, a deeper understanding of the technology infrastructure was acquired as well as the processes carried out in the value chain of a space-based ADS-B company.

En el contexto del proyecto Kepler, desarrollo de algunos de los sistemas que permitirán los enlaces de datos y medidas de distancia usando láseres modulados entre satélites.

The existing global digital divide between the different geographic areas, leads to almost half of the world’s population lacking access to a reliable Internet connection. OneWeb, a global telecommunications company, aims to deploy an initial constellation of 648 satellites in low Earth orbit (LEO) to provide high-speed and low-latency connectivity to governments, businesses and communities around the world. Therefore, this thesis focuses on the study of the benefits provided by this orbit in the telecommunications field, for the subsequent analysis and development of OneWeb’s business model, by means of the CANVAS methodology. This project is integrated within the DISCOVERER framework, a European project dedicated to the research of innovative technologies for its application in the lowest orbits (VLEO), in which UPC is involved focusing on the market analysis to solve the existing market challenge.

This work has been supported by the Spanish Science, Research and Innovation Plan(MINECO) with Project Codes TIN2014-55413-C2-1-P and TEC2017-85244-C2-2-P andby Unidad de Excelencia Maria de Maeztu MDM-2016-0600 financed by the Agencia Es-tatal de Investigaci ́on, Spain.

L’any 2019 es va caracteritzar per la planificació de l’execució del segon dividend digital, que, a més d’una replanificació de les freqüències dels canals de televisió digital terrestre, preveu, en un termini d’uns tres anys, la renovació total del parc de receptors, tot derivat dels esforços esmerçats per al desplegament per fases de la cinquena generació de comunicacions mòbils, l’anomenada 5G., Postprint (published version)

© 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., Earth Observation missions have increasingly demanding requirements, i.e., higher spatial resolutions and SNR, and lower revisit times, etc. High-resolution images have to be captured with precise pointing accuracy which is achieved by the satellite's attitude determination and control system (ADCS). This subsystem embeds multiple sensors and actuators capable of changing the satellite attitude by changing the torque applied to the platform. In small satellites, magnetorquers, and more recently reaction wheels as well, are the most frequently used actuators. These components fulfill their main purpose, but exhibit some drawbacks, notably a nonconstant jitter that provokes nondesired oscillations of the spacecraft, which may result in blurred images. This work presents a deblurring methodology that uses data coming from the ADCS sensors to infer a spatially variant point-spread function. Moreover, the impact of having a lower temporal resolution than the ideal on the sensors is analyzed and a method is presented to improve it., This work has been supported by project "Sensing with pioneering opportunistic techniques-SPOT," Spanish Agencia Estatal de Investigación Grant RTI2018-099008-B-C21 and EU ERDF funds, and UPC-CommSensLab María de Maeztu Unit Grant MDM-2016-0600., Peer Reviewed, Postprint (author's final draft)

Amb l'increment del número de constel·lacions de satèl·lits, cada cop es necessiten més Ground Stations per tal de controlar-les. Això dificulta més i més la seva gestió i operació, implicant també un augment en la càrrega de treball pels operadors, fent així més propensos els errors. És per això que cada vegada és més important l'automatització a l'hora de controlar el Ground Segment. El Nano-Satellite and Payload Laboratory (NanoSat Lab) també ha apostat per aquesta tecnología alhora que estén la seva xarxa de Ground Stations. Aquest treball presenta l'arquitectura de software necessària per aconseguir un sistema modular i escalable que fa front a l'actual increment de demanda. El disseny d'aquesta arquitectura està detallat en les següents seccions, fent incís també en diferents experiències viscudes durant el desplegament del software. Així mateix, es presenten els resultats del funcionament del sistema. Finalment, el treball acaba amb una avaluació de feina futura i recomanacions., With the increasing number of satellite constellations, the number of Ground Stations needed to control them has risen dramatically. This complicates their management and operation, resulting in an increase of the workload for operators, which in turn become more prone to commit errors. For this reason, automation is becoming more important when controlling the Ground Segment. The Nano-Satellite and Payload Laboratory (NanoSat Lab) has also followed this trend, extending its current Ground Station network. This work presents the software architecture needed to achieve a modular and scalable system that copes with this current demanding increase. The design of this architecture is detailed in the following sections, highlighting the different experiences during the deployment of the software. Additionally, results of the system performance are presented as well. Finally, the work is concluded with future tasks and recommendations.

The AOCS is the system needed in order to know the orientation of our space vehicle and be able to control it so it is possible to reach the desired pointing and given this, began with the execution of scientific missions. In the case of this project the AOCS system will be only consists of a gravity boom, so the attitude control of this 3U CubeSat will be passive trough the gravity gradient torque. For the simulations that take place in this study, the software MATLAB will be used as a vehicle to analyse the AOCS system. This same software will allow to determine the inertia and other characteristics of the 3U Cubesat, which will be fundamental to the subsequent calculations in order to obtain the gravity boom influence in the spacecraft stabilization. This document will explain the physics behind the spacecraft model, the calculations needed in order to obtain its inertia values and also the equations needed to model the space environment and the forces that are needed for the chosen analysis. Also the algorithms designed in MatLab will be presented in form of Annex, being the calculations for the plots, inertia, angular deviations, ... The results have the goal of determining if the use of the gravity boom is enough to control the attitude of the Cubesat, so diverse configurations for the satellite will be simulated, with variations on the mass of the gravity boom and the length of the cable that links it with the CubeSat body. As it shows in the conclusion section, the configuration where mgb= 1 kg and lcb= 2.5 m seems to meets the requirements of pointing for medium/low accuracy, but if the use of some sensor was to be considered (such as sun sensor or star trackers), missions with the need for a high accuracy system could be feasible as the nadir pointing obtained has a very low angular deviation. However, even though the results for this values are successful, any increase in both variables characterstics lead to the instability of the CubeSat and can not be

This Maser Thesis is part of a projectinvestigation from the DISEN group. Within this program, the CubeSat project aims to connect several satellites to improve optical data transmission in the space. This Master Thesis mainly covers the design and simulation of a free-space optical communication system intended for a data transfer of at least 1 Mbit/s. System Requirements inherent to its application on free-space were the starting point to design system power needs. Free-space optical communication demands high power as well as specific precision and speed in a limited board. The high-speed transmitter is composed of a VCSEL whereas the receiver is composed of a PIN photodiode. Up to three different switches have been simulated in MULTISIM software and compared in the following fields: - Frequency response - Minimum noise contribution - Performance with available power source Most of the time spend in this thesis, has been dedicated to obtain knowledge about the free-space optical communication properties. Hundreds of components have been investigated and its datasheets compared according to FSO properties. As the MULTISIM software selected for the simulations is based on PSPICE models of the components, the design of these models has been widely studied. The selected ones have been simulated to ensure the functionality of the circuit. The frequency analysis will determinant to select one of the transistors. In this Master Thesis, the cut-off frequency term will be widely used to describe the bandwidth of each transistor. This thesis has resulted in an optimized emitter and receiver circuits for high-speed FSO.

The 3-CAT4 is a 1U Cubesat developed by the NanoSat Lab (UPC) to be launched by the European Space Agency in 2019. In this TFG, the structural analysis and tests required by ESA before the launch of the Cubesat will be designed and performed., In the past decades the tendency to make space available has led to a new world wide situation, the new space, with the small satellites as their maximum exponent. Inside that group of satellites, Nanosatellites are the most commonly used among students and, in the case of the Universitat Politècnica de Catalunya, it is not different. NanoSat Lab Team, with base in Campus Nord, has believed ever since its creation in this technology. With the design and development of three nanosatellites, one of which was put into orbit in 2016, it is the most experienced student team involved in CubeSats in Catalunya. The new NanoSat Lab project, 3Cat-4 mission, was selected for the ESA program Fly Your Satellite! and it is planned to be launched by the end of 2018. This thesis is set to conduct the works related to the integration of the CAD model of the satellite and the analysis of the structural behaviour of the satellite during the launch.

En este proyecto de fin de grado se ha implementado un servidor SAP/SDPque permiteanunciar sesionesen tiempo realpara el paso de satélites de órbita baja de la Terrassa Ground Stationa los usuarios que lo necesiten. Con el escenario diseñado e implementado,se crea un túnel VPNconel protocolo de comunicacionesPPTPpara el envío de los paquetes multicast, ya que Internet no está preparado para el tráfico de dichos paquetes. Los clientes se conectan dinámicamente algrupo multicastgracias aque en el servidor está implementado IGMPproxyymediante un programaen Python pueden ver de forma gráfica el paso de los satélites y la información de ellos gracias almódulocurses.A la hora de realizar las pruebas en un entorno controlado se ha utilizado un escenario de red virtual que trabaja sobre Linux (VNX) con contendores LXC. El uso de VNX con LXC ha permitido crear y destruir escenarios virtuales con diferentes dispositivos y redes de manera rápida en lenguaje XML.