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LoRaWAN has emerged as a fast growing technology of choice in the Internet of Things (IoT) field, emerging as a crucial component of Low Power Wide Area Networks (LPWANs). The deployment of a single access point can extend coverage to thousands of devices, resulting in a cost-effective and easy-to-maintain network infrastructure. LoRaWAN's long reach, combined with its efficient power consumption and resilient performance, has driven its popularity in a wide range of IoT applications. In particular, it has been adopted widely in sectors such as smart cities, agriculture and environmental monitoring, where the need for reliable, long-range connectivity is paramount. Due to these advances, the project has been initiated to establish a LoRaWAN network within the Baix Llobregat campus in Castelldefels. The main objective of this project is to create a fully operational network, in addition to integrating an IoT platform that allows to visualize the telemetry captured by the sensors. By analyzing the behavior of the network and assessing the reliability of connectivity through coverage tests performed at various points of interest, the project aims to obtain valuable information about the performance of the network from the perspective of the devices involved. It has been seen that for a configuration of SF12 in the devices, connectivity is guaranteed, however, in the area near the river, the error rate is high. In addition, the correct performance of the implemented networks servers has been verified, both the public version of The Things Network and the open source version of The Things Stack on a local server. Finally, the integration with the IoT Thingsboard platform was completed, allowing the creation of graphs to monitor the collected data, as well as the implementation of rule chains to process the data and send actions to the sensors in case of alarm activation.

Hyperspectral imaging is a novel technology for acquiring an image at a large number of wavelengths, thus allowing the study of spectral and spatial details of a sample under analysis. This technology has emerged as a promising imaging modality to be used as a diagnostic tool in several medical applications where spectral information is relevant. In this paper, we outline our most recent achievements in this field. Firstly, hyperspectral imaging systems developed to improve non-invasive diagnosis of skin cancer, consisting of digital silicon and InGaAs cameras and light emitting diodes, are described. Secondly, we present our last advances using hyperspectral technology together with confocal microscopy to improve the diagnosis of blood diseases, in particular, hemoglobinopathies such as thalassemia and cell membrane diseases such as hereditary spherocytosis. Finally, new insights on these topics are discussed. This project has been funded by the Agencia Estatal de Investigación (AEI) (PID2020-112527RB-I00 / AEI / 10.13039/501100011033). L R-B thanks the Ministry of Science, Innovation and Universities for the PhD (FPI) grant she has received.

In 2018, IATA Resolution 753 came into force. This obliges airlines to track baggage at various specific points along its route. For the time being, baggage identification by reading barcode labels is mainly used. Although this technology meets all the requirements of IATA, it has certain limitations and does not allow for exhaustive baggage tracking, and still relies on the actions of many human personnel who are susceptible to errors, resulting in lost baggage, customer dissatisfaction, additional costs for the airline and aircraft delays. The project aims to study the feasibility of implementing radio frequency identification (RFID) technology for baggage management and tracking in the Spanish airport network. Given that the technology has been under development for years, its cost is relatively low, and it could be used in a hybrid way with current baggage identification systems. This would reduce the rate of baggage loss, optimise the loading and unloading of aircraft and ease the adoption of Resolution 753. To this end, an infrastructure implementation plan has been developed for the most important airports in Spain. The results determine that it is advisable to implement RFID in the airports with the highest volume of traffic in Spain.

The Remote sensing and Interference detector with radiomeTry and vegetation Analysis (RITA) is one of the Remote Sensing payloads selected as winners of the 2nd GRSS Student Grand Challenge in 2019, to fly on board of the 3U AlainSat-1. This CubeSat is being developed by the National Space Science and Technology Center (NSSTC), United Arab Emirates University. RITA has been designed as an academic mission, which brings together students from different backgrounds in a joint effort to apply very distinct sensors in an Earth Observation mission, fusing their results to obtain higher-accuracy measurements. The main payload used in RITA is a Total Power Radiometer such as the one on board the FSSCat mission. With these radiometric measurements, soil moisture and ice thickness will be obtained. To better characterize the extensive Radio-Frequency Interferences received by EO satellites in protected bands, several RFI Detection and Classification algorithms will be included to generate a worldwide map of RFI. As a novel addition to the 3Cat family of satellites and payloads, a hyper-spectral camera with 25 bands ranging from 600 to 975 nm will be used to obtain several indexes related to vegetation. By linking these measurements with the soil moisture obtained from the MWR, pixel downscaling can be attempted. Finally, a custom- developed LoRa transceiver will be included to provide a multi-level approach to in-situ sensors: On-demand executions of the other payloads will be able to be triggered from ground sensors if necessary, as well as simple reception of other measurements that will complement the ones obtained on the satellite. The antennas for both the MWR and the LoRa experiments have been developed in-house, and will span the entirety of one of the 3U sides of the satellite. In this work, the latest development advances will be presented, together with an updated system overview and information about the operations that will be conducted. Results obtained from the test campaign are also presented in the conference.

La necessitat urgent de comprendre més el funcionament dels ecosistemes marins posa en importància la recopilació de dades per a posteriors anàlisis. A causa de l'entorn, suposa un gran repte la recuperació d'aquestes dades sense la necessitat d'accedir físicament als dispositius d'adquisició de dades o la retirada d'aquestes dades, això fa que estiguem en una recerca constant de tecnologies que permetin transmetre aquesta informació sense ús de llargs i costosos cables submarins. Habitualment les comunicacions sense fil submarines s'implementen mitjançant interfícies acústiques. Aquest projecte té com a objectiu caracteritzar i conèixer les limitacions de diferents interfícies de comunicació com Bluetooth o Wi-Fi al medi aquàtic i d'aquesta manera identificar en quines aplicacions o escenaris aquestes tecnologies seguirien sent vàlides. Atesa la viabilitat d'aquestes comunicacions sense fil i les seves limitacions, es presenta el desenvolupament d'un dispositiu que permeti i faciliti la transmissió de les dades adquirides des de les plataformes d'observació submarines. S'ha investigat com aconseguir l'objectiu d'aquest dispositiu i se li ha començat, asseient així una base, al desenvolupament d'una aplicació per aconseguir aquesta finalitat. La urgente necesidad de comprender en mayor medida el funcionamiento de los ecosistemas marinos pone en importancia la recopilación de datos para posteriores análisis. Debido al entorno, supone un gran reto la recuperación de estos datos sin la necesidad de acceder físicamente a los dispositivos de adquisición de datos o la retirada de estos, esto hace que estemos en una constante búsqueda de tecnologías que permitan transmitir dicha información sin el uso de largos y costosos cables submarinos. Habitualmente las comunicaciones inalámbricas submarinas se implementan mediante interfaces acústicas. El presente proyecto tiene como objetivo caracterizar y conocer las limitaciones de diferentes interfaces de comunicación como Bluetooth o Wi-Fi en el medio acuático y de esta manera identificar en que aplicaciones o escenarios dichas tecnologías seguirían siendo válidas. Ya vista la viabilidad de estas comunicaciones inalámbricas y sus limitaciones, se presenta el desarrollo de un dispositivo que permita y facilite la transmisión de los datos adquiridos desde las plataformas de observación submarinas. Se ha investigado como conseguir el objetivo de este dispositivo y se le ha dado comienzo, sentando así una base, al desarrollo de una aplicación para lograr ese fin. The urgent need to better understand the functioning of marine ecosystems makes it important to collect data for further analysis. Due to the environment, it is a great challenge to recover this data without the need to physically access the data acquisition devices or the removal of these, this means that we are in a constant search for technologies that allow transmitting said information without the use of long and expensive submarine cables. Underwater wireless communications are typically implemented using acoustic interfaces. The objective of this project is to characterize and understand the limitations of different communication interfaces such as Bluetooth or Wi-Fi in the aquatic environment and thus identify in which applications or scenarios these technologies would continue to be valid. Having seen the feasibility of these wireless communications and their limitations, the development of a device that allows and facilitates the transmission of data acquired from underwater observation platforms is presented. Research has been carried out on how to achieve the objective of this device and the development of an application to achieve this goal has been started, thus laying a foundation.

©2022 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. This paper presents an embroidered textile frequency-splitting microwave sensor based on a pair of identical stepped-impedance resonators (SIRs) loading a microstrip transmission line. The sensor is implemented by means of conductive threads. The sensing region of the proposed structure is the capacitive square patch of one of the SIRs. If such region is kept unaltered, the structure is symmetric, and the frequency response (transmission coefficient) exhibits a single transmission zero. However, if symmetry is broken (e.g., through liquid absorption in the sensing region), the frequency response of the proposed sensor exhibits two transmission zeros (frequency splitting). The difference (in frequency and magnitude) between such zeros (or notches) is intimately related to the dielectric properties of the absorbed liquids to be sensed / detected. The proposed sensing structure is applied to the detection of deionized (DI) water absorption, and to the quantification of the number of DI water drops. The maximum measured sensitivity is found to be 2.70 MHz /µl and 0.03 dB /µl for the incremental frequency and incremental magnitude of the notches. This work was supported by MICIIN-Spain (projects PID2019-103904RB-I00, TEC2016-79465-R, and PDC2021-121085-I00),Generalitat de Catalunya (project 2017SGR-1159), Institució Catalana de Recerca i Estudis Avançats (who awarded Ferran Martín), and by FEDER funds.

Metallic glasses have a disordered structure, out of equilibrium, which does not stop changing towards a more stable state. This physical aging process, driven by structural relaxation, has been investigated for some time on different metallic glasses because of the important relation it has with the dynamics of the vitreous state and the macroscopic mechanical properties. Recently, a technique that enables to observe the microscopic dynamics of metallic glasses has been developed, X-Ray Photon Correlation Spectroscopy. This experimental procedure allows to see the structural relaxation of glasses at the atomic length scale, using the scattered speckle patterns from coherent X-Ray beams. In this work, a metallic glass forming alloy, Pd{43}-Ni{10}-Cu{27}-P{20}, will be studied. The slow, microscopic relaxation dynamics of this material were previously characterized, showing complex intermittent phenomena in the glass state [Phys. Rev. Lett. 115, 175701 (2015)]. Thanks to the new developments in synchrotron coherent X-ray beamlines, in this work we extend the characterization of the microscopic dynamics to the glass transition and supercooled liquid regions, revealing how is the change from out of equilibrium to equilibrium dynamics of this system. Los vidrios metálicos tienen una estructura desordenada, fuera del equilibrio, que no para de cambiar hacia un estado más estable. Este proceso de envejecimiento físico, impulsado por la relajación estructural, ha sido investigado durante mucho tiempo en diferentes vidrios metálicos debido a la importante relación que tiene con la dinámica del estado vítreo y las propiedades mecánicas macroscópicas. Recientemente, se ha desarrollado una técnica que permite observar la dinámica microscópica de los vidrios metálicos, la Espectroscopia de Correlación de Fotones de Rayos X. Este procedimiento experimental permite ver la relajación estructural de los vidrios en la escala de longitud atómica, utilizando los patrones de motas dispersas de haces coherentes de rayos X. \ par En este trabajo, se estudiará una aleación de formación de vidrio metálico, Pd {43} -Ni {10} -Cu {27} -P {20}. La dinámica de relajación lenta y microscópica de este material fue previamente caracterizada, mostrando complejos fenómenos intermitentes en el estado vítreo [Phys. Rev. Lett. 115, 175701 (2015)]. Gracias a los nuevos desarrollos en líneas de rayos X coherentes de sincrotrón, en este trabajo ampliamos la caracterización de la dinámica microscópica a la transición vítrea y regiones líquidas superenfriadas, revelando cómo es el cambio de dinámica fuera de equilibrio a dinámica de equilibrio de este sistema. Els vidres metàl·lics tenen una estructura desordenada, fora d'equilibri, que no para de canviar cap a un estat més estable. Aquest procés d'envelliment físic, impulsat per la relaxació estructural, s'ha investigat durant un cert temps en diferents ulleres metàl·liques a causa de la important relació que té amb la dinàmica de l'estat vítre i les propietats mecàniques macroscòpiques. Recentment s'ha desenvolupat una tècnica que permet observar la dinàmica microscòpica dels vidres metàl·lics, l'espectroscòpia de correlació de fotons de raigs X. Aquest procediment experimental permet veure la relaxació estructural de les ulleres a escala de longitud atòmica, utilitzant els patrons dispersos de taques de feixos de raigs X coherents. En aquest treball, s'estudiarà un aliatge de formació de vidre metàl·lic, Pd {43} -Ni {10} -Cu {27} -P{20. La dinàmica de relaxació lenta i microscòpica d'aquest material es caracteritzava prèviament, mostrant fenòmens intermitents complexos en estat de vidre [Phys. Rev. Lett. 115, 175701 (2015)]. Gràcies als nous desenvolupaments en línies de feixos de raigs X coherents de sincrotró, en aquest treball estenem la caracterització de la dinàmica microscòpica a la transició vítrea i a les regions líquides superrefredades, revelant com és el canvi de la dinàmica d'equilibri a la dinàmica d'aquest sistema.

Electrical and Telecommunication Engineering is nowadays playing a fundamental role in biomedical research and its applications. Microwave and Antenna Group at EPFL are working resolutely to help in this vital field for society, as it has been unfortunately proven once again during the sanitary crisis caused by the COVID-19 outbreak in the last months. With this final degree thesis, I have tried to make my humble contribution to this broad topic, focusing on the field of Radio Frequency Identification (RFID). To do so, the main objective of this work was to study the frequency splitting phenomenon and verify whether it is plausible to identify a 2mm electrically small passive loop antenna using another active antenna of the same characteristics. It has been found that for close distances with no dielectric boundaries (up to 2.5mm for this configuration), analysing the frequency splitting phenomenon is an effective way to correctly confirm the presence of the passive antenna (or transponder), and it is even possible to determine its distance relative to the active antenna (or reader). When a dielectric environment is added, frequency splitting can be detected as well. However, in this case, the detectable distance range decreases due to the high relative permittivity conditions. These findings lead to a feasible way to implement a low-complexity 1-bit transponder for short-range applications. La Ingeniería Eléctrica y de Telecomunicaciones tiene actualmente un papel fundamental en la investigación biomédica y sus aplicaciones. El Grupo de Microondas y Antenas de la EPFL trabaja decididamente para ayudar en este campo vital para la sociedad, como ha sido lamentablemente demostrado una vez más durante la crisis sanitaria provocada por la pandemia de COVID-19 en los últimos meses. Con esta tesis de fin de grado, he tratado de hacer mi humilde aportación a este amplio tema, centrándome en el campo de la Identificación por Radiofrecuencia (RFID). Para ello, el objetivo principal de este trabajo ha sido estudiar el fenómeno de división frecuencial (conocido en inglés como frequency splitting) y verificar si es posible identificar una antena pasiva eléctricamente pequeña del tipo espira elemental de 2 mm utilizando otra antena activa de las mismas características. Se ha encontrado que para distancias cortas sin condiciones de dieléctrico (hasta 2.5 mm para esta configuración), analizar el fenómeno de división frecuencial es una forma efectiva de confirmar correctamente la presencia de la antena pasiva (o transpondedor), e incluso es posible determinar su distancia relativa a la antena activa (o lector). Cuando se añade un entorno dieléctrico, también se puede detectar la división frecuencial, pero en distancias más limitadas para condiciones de permitividad relativa alta. Estos hallazgos conducen a una forma viable de implementar un transpondedor de 1 bit de baja complejidad para aplicaciones de corto alcance. L'Enginyeria Elèctrica i de Telecomunicacions té actualment un paper fonamental en la recerca biomèdica i les seves aplicacions. El Grup de Microones i Antenes (MAG) de l'EPFL treballa decididament per tal d'ajudar en aquesta àrea vital per al conjunt de la societat, com ha estat malauradament demostrat una vegada més durant la crisi sanitària derivada de la pandèmia causada pel COVID-19 els darrers mesos. Amb aquest treball de fi de grau, he intentat fer la meva modesta aportació a aquest ampli tema, centrant-me en el camp de la Identificació per Ràdio Freqüència (RFID). A tal efecte, el principal objectiu d'aquest treball ha estat estudiar el fenomen de la divisió freqüencial (conegut en anglès com frequency splitting) i verificar si és possible identificar una antena elèctricament petita passiva del tipus espira elemental de 2mm de diàmetre mitjançant una altra antena activa de les mateixes característiques. S'ha comprovat que per a distàncies properes sense condicions de dielèctric (fins a 2,5mm en aquesta configuració), analitzar el fenomen de divisió freqüencial és una manera eficaç de confirmar correctament la presència de l'antena passiva (o transponedor), i és fins i tot possible determinar-ne la distància respecte a l'antena activa (o lector). Quan s'hi afegeix un entorn dielèctric, el fenomen de la divisió freqüencial pot ser detectat també, encara que en distàncies més limitades en condicions de permitivitats relatives elevades. Aquests resultats porten a una implementació viable d'un detector d'un bit de baixa complexitat per a aplicacions de curt abast.

Radio frequency interference (RFI) is an increasing problem in microwave radiometry, particularly for Earth observation, because the antennas are pointing toward the Earth. RFI has been observed at the L-band in European Space Agency's (ESA's) Soil Moisture and Ocean Salinity (SMOS) Earth Explorer mission, National Aeronautics and Space Administration's (NASA's) Soil Moisture Active and Passive (SMAP) and Aquarius missions, and Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) and WindSat missions at 10.7 and 18.7 GHz (Misra and de Matthaeis, 2014). Therefore, dedicated onboard systems are, nowadays, a must to detect and remove contaminated measurements, improving radiometric accuracy and increasing the spatial coverage. In this work, a novel detection technique, specially tailored for synthetic aperture interferometric radiometers (SAIRs), is proposed and its performance analyzed. It is based on the change of the shape of the cross correlation function at lags different from zero under the presence of RFI. The performance of the proposed technique is compared to other common RFI detection algorithms, and its limitations and advantages are discussed. Postcorrelation detection performance is found to outperform other commonly used algorithms, such as kurtosis. In addition, it presents some convenient properties for its practical application in correlation and real aperture radiometers. This work was supported by “SPOTSensing With Pioneering Opportunistic Techniques” under Grant RTI2018 -099008-B-C21/AEI/10.13039/501100011033.

Filtering microwave amplifiers have become a topic of interest because of the need for devices capable of isolating the system itself and avoiding interference from other systems. Key subsystems in communication receivers and transmitters are the microwave amplifiers, either low-noise amplifiers (LNA) or solid-state power amplifiers (SSPA). Different topologies have been proposed in the last years and a big research effort has been devoted to filtering structures, either in the input matching network (IMN) or output matching network (OMN). The subject of study of this master thesis is the design of a filtering microwave amplifier to be operated at 4 GHz. As a continuation of my bachelor final project -where the subject of study was the design of a frequency-switchable microwave amplifier that could be operated at three different frequencies (3.2 GHz, 4 GHz and 4.8 GHz) in the 5G band- this master thesis proposes a methodology to improve the filtering capabilities of such components. To this end, several filtering structures are studied, taking into account the trade-off between performance and circuit size. The theoretical design procedure is studied, providing insights in the problems that can appear for different filtering topologies. The IMN is based on a simple line-stub structure, and the OMN is a filtering structure which is simulated and fabricated in multiple forms to provide insights in the structures available. The amplifier behavior is simulated using circuit and 2.5D electromagnetic simulations and optimized. The amplifier was fabricated on a conventional microwave substrate, and its S parameters and noise figure were measured and compared to simulations, showing a good agreement with simulations. Los amplificadores de microondas se han convertido en un tema de interés a causa de la necesidad de componentes capaces de aislar el sistema frente a interferencias de otros circuitos. Un ejemplo de subsistemas destacables en transmisores y receptores de comunicación son los amplificadores de microondas, tanto de bajo ruido (LNA) como de potencia (PA). Durante los últimos años se han propuesto diferentes tipos de filtraje y se ha invertido mucha investigación en los componentes, tanto en la red de adaptación de entrada (IMN) como de salida (OMN). El tema de estudio de esta tesis de máster es el diseño de un amplificador de microondas filtrante a la frecuencia de 4 GHz. Como continuación de mi trabajo de fin de grado \cite{TFGPol} -donde el tema de estudia era el diseño de un amplificador de microondas conmutable que se podía utilizar a tres frecuencias distintas (3.2 GHz, 4 GHz y 4.8 GHz) en la banda de 5G-, esta tesis de máster propone una metodología para mejorar las capacidades filtrantes de estos componentes. Con este objetivo, se estudian diversas estructuras filtrantes, teniendo en cuenta el balance entre resultados y tamaño del circuito. Se estudia el método de diseño teórico, aportando detalles sobre los problemas que pueden aparecer en diversas tipologías de filtro. La red de entrada (IMN) se basa en una estructura simple de línea-stub y la red de salida (OMN) es una estructura filtrante, que es simulada y fabricada utilizando diferentes formas para aportar detalles sobre las diversas estructuras disponibles. Se ha simulado el comportamiento del amplificador utilizando simulaciones 2.5D electromagnéticas y se ha optimizado. El amplificador se fabricó en un sustrato de microondas convencional y sus parámetros S y factor de ruido F fueron medidos y comparados con las simulaciones, mostrando una buena concordancia entre ambos resultados. Els amplificadors filtrants de microones s'han convertit en un tema d'interès a causa de la necessitat de components capaços d'aïllar el sistema d'interferències d'altres circuits. Un exemple de subsistemes destacables en transmissors i receptors de comunicacions són els amplificadors de microones, tant de baix soroll (LNA) com de potència (PA). Durant els últims anys s'han proposat diferents estructures filtrants i s'ha dut a terme molta investigació, tant en les xarxes d'entrada (IMN) com en les xarxes de sortida (OMN). El tema d'estudi d'aquesta tesi de màster és el disseny d'un amplificador de microones filtrant a la freqüència de 4 GHz. Com a continuació del meu treball de fi de grau -on el tema d'estudi era el disseny d'un amplificador de microones commutable que es podia utilitzar a tres freqüències diferents (3.2 GHz, 4 GHz i 4.8 GHz) a la banda de 5G-, aquesta tesi de màster proposa una metodologia per millorar les capacitats filtrants d'aquests components. Amb aquest objectiu, s'estudien diverses estructures filtrants, tenint en compte el balanç entre resultats i mida del circuit. S'estudia el mètode de disseny teòric, aportant detalls sobre els problemes que poden aparèixer en diverses tipologies de filtre. La xarxa d'entrada (IMN) es basa en una estructura simple de línia-stub i la xarxa de sortida (OMN) és una estructura filtrant, que és simulada i fabricada utilitzant diverses formes per aportar detalls sobre les diverses estructures disponibles. S'ha simulat el comportament de l'amplificador utilitzant simulacions 2.5D electromagnètiques i s'ha optimitzat. S'ha fabricat l'amplificador utilitzant un substrat de microones convencional i els seus paràmetres S i factor de soroll F s'han mesurat comparats amb les simulacions, mostrant una bona concordança entre ambdós resultats.

Metallic glasses have a disordered structure, out of equilibrium, which does not stop changing towards a more stable state. This physical aging process, driven by structural relaxation, has been investigated for some time on different metallic glasses because of the important relation it has with the dynamics of the vitreous state and the macroscopic mechanical properties. Recently, a technique that enables to observe the microscopic dynamics of metallic glasses has been developed, X-Ray Photon Correlation Spectroscopy. This experimental procedure allows to see the structural relaxation of glasses at the atomic length scale, using the scattered speckle patterns from coherent X-Ray beams. In this work, a metallic glass forming alloy, Pd{43}-Ni{10}-Cu{27}-P{20}, will be studied. The slow, microscopic relaxation dynamics of this material were previously characterized, showing complex intermittent phenomena in the glass state [Phys. Rev. Lett. 115, 175701 (2015)]. Thanks to the new developments in synchrotron coherent X-ray beamlines, in this work we extend the characterization of the microscopic dynamics to the glass transition and supercooled liquid regions, revealing how is the change from out of equilibrium to equilibrium dynamics of this system. Los vidrios metálicos tienen una estructura desordenada, fuera del equilibrio, que no para de cambiar hacia un estado más estable. Este proceso de envejecimiento físico, impulsado por la relajación estructural, ha sido investigado durante mucho tiempo en diferentes vidrios metálicos debido a la importante relación que tiene con la dinámica del estado vítreo y las propiedades mecánicas macroscópicas. Recientemente, se ha desarrollado una técnica que permite observar la dinámica microscópica de los vidrios metálicos, la Espectroscopia de Correlación de Fotones de Rayos X. Este procedimiento experimental permite ver la relajación estructural de los vidrios en la escala de longitud atómica, utilizando los patrones de motas dispersas de haces coherentes de rayos X. \ par En este trabajo, se estudiará una aleación de formación de vidrio metálico, Pd {43} -Ni {10} -Cu {27} -P {20}. La dinámica de relajación lenta y microscópica de este material fue previamente caracterizada, mostrando complejos fenómenos intermitentes en el estado vítreo [Phys. Rev. Lett. 115, 175701 (2015)]. Gracias a los nuevos desarrollos en líneas de rayos X coherentes de sincrotrón, en este trabajo ampliamos la caracterización de la dinámica microscópica a la transición vítrea y regiones líquidas superenfriadas, revelando cómo es el cambio de dinámica fuera de equilibrio a dinámica de equilibrio de este sistema. Els vidres metàl·lics tenen una estructura desordenada, fora d'equilibri, que no para de canviar cap a un estat més estable. Aquest procés d'envelliment físic, impulsat per la relaxació estructural, s'ha investigat durant un cert temps en diferents ulleres metàl·liques a causa de la important relació que té amb la dinàmica de l'estat vítre i les propietats mecàniques macroscòpiques. Recentment s'ha desenvolupat una tècnica que permet observar la dinàmica microscòpica dels vidres metàl·lics, l'espectroscòpia de correlació de fotons de raigs X. Aquest procediment experimental permet veure la relaxació estructural de les ulleres a escala de longitud atòmica, utilitzant els patrons dispersos de taques de feixos de raigs X coherents. En aquest treball, s'estudiarà un aliatge de formació de vidre metàl·lic, Pd {43} -Ni {10} -Cu {27} -P{20. La dinàmica de relaxació lenta i microscòpica d'aquest material es caracteritzava prèviament, mostrant fenòmens intermitents complexos en estat de vidre [Phys. Rev. Lett. 115, 175701 (2015)]. Gràcies als nous desenvolupaments en línies de feixos de raigs X coherents de sincrotró, en aquest treball estenem la caracterització de la dinàmica microscòpica a la transició vítrea i a les regions líquides superrefredades, revelant com és el canvi de la dinàmica d'equilibri a la dinàmica d'aquest sistema.

Aquest projecte sorgeix de la voluntat de transformació tecnològica per part de la Direcció de Instal·lacions, Equipaments i Infraestructures de la Mútua Col·laboradora de la Seguretat Social Asepeyo, per millorar els seus processos i gestió d’actius en un centre assistencial, mitjançant la implantació de la tecnologia de identitat per ràdio freqüència RFID. L’elaboració d’aquest estudi ha estat dut a terme com a projecte final de grau d’Enginyeria en Tecnologies Industrials (GRETI). La identitat per ràdio freqüència ha experimentat un creixement molt important ens els últims anys, arran de l’explotació d’aquesta tecnologia per grans empreses tant del sector del “retail”, com de la banca, o del sector de la telefonia mòbil, ja que la possibilitat de tenir traçabilitat, control d’actius, inventaris o pagaments en temps real, fa molt atractiva aquesta tecnologia en vers al tradicional codi de barres, cada vegada més en des ús, però que l’empresa Asepeyo està pensant d’implantar. L’estudi del projecte és centrarà en analitzar aquesta tecnologia, coneixent a fons el seu funcionament per tal de poder fer una valoració de la implantació d’aquesta, en un centre assistencial d’Asepeyo, fent un anàlisi quantitatiu i un estudi econòmic de tots i cada un dels elements que intervenen, així com analitzar el cost que suposaria la implantació en tot l’àmbit nacional i concloure si és recomanable o no, la implantació de la identitat per radiofreqüència RFID, en front de la tecnologia de les màquines tèrmiques amb codi de barres, que és el que es pretén dur a terme, en un principi l’empresa Asepeyo. Les eines que s’utilitzaran per elaborar el present estudi seran els coneixements adquirits al grau d’Enginyeria en Tecnologies Industrials (GRETI) realitzat a l’Escola Tècnica Superior d’Enginyeria Industrial Aeroespacial i Audiovisual de Terrassa.

[CASTELLÀ] El objetivo de este proyecto es el estudio y desarrollo de un sistema de recolección de energía de radiofrecuencia, siendo capaz de rectificar esta energía eléctrica a corriente continua para poderla almacenar o utilizarla para alimentar un dispositivo en concreto. El sistema está pensado para energizar dispositivos de muy bajo consumo como las redes de sensores inalámbricos(WSN). Una problemática de esta red es su autosostenibilidad debido a la vida limitada de la batería. La estructura del sistema de captación de radiofrecuencia está formada por la antena, el circuito de acoplamiento o adaptación de impedancias, el circuito multiplicador-rectificador y por último el circuito de nivelación o filtrador. Dentro del proyecto, se explican los diferentes tipos o variaciones de los circuitos nombrados. Finalmente, se realizan simulaciones y un análisis experimental del circuito impreso (PCB) diseñado, donde se conectan los diferentes circuitos seleccionados que conforman el sistema de recolección, el cual está pensado para la cosecha de radiofrecuencia de la banda de los 868MHz. Mediante estos procesos, se consigue demostrar el funcionamiento del sistema además de sus ventajas y limitaciones. [ANGLÈS] The aim of this project is the study and development of a radio frequency energy harvesting, being able to rectify this electrical energy to direct current in order to store it or use it to power a specific device. The system is designed to power low devices such as Wireless Sensor Networks (WSN). The problem with this network is its self-sustainability due to the limited life of the battery. The structure of the radio frequency collection system is formed by the antenna, the impedance matching circuit, the multiplier-rectifier circuit and finally the levelling or filtering circuit. In the project, the different types or variations of the named circuits are explained. Finally, simulations and an experimental analysis of the designed printed circuit (PCB) are made, where the different selected circuits that are part of the harvesting system are connected, which is designed for harvest the radio frequency of the 868MHz band. Through these processes, it is possible to demonstrate the operation, advantages and limitations of the system.

En este proyecto de investigación, se han diseñado y simulado dos antenas RFID, que funcionan con chips diferentes y que resuenan a una frecuencia de 13.56 MHz, que es la frecuencia utilizada para la tecnología NFC. Actualmente, encontramos este tipo de tecnología en tarjetas de crédito, llaves y etiquetas de ropa, que nos ayudan en nuestra vida cuotidiana. Concretamente, este tipo de antenas en ropa y en la propia piel humana se están empezando a investigar, por lo que su cantidad en el mercado es reducida. Una vez hecho el diseño de las antenas, se ha procedido a realizar sus respectivas simulaciones con el software ADS de Keysight Technologies y se han mostrado los resultados de las antenas con ambos chips. Con los resultados obtenidos, en trabajos futuros, se implementará la antena diseñada con mejores resultados en un tejano y se realizarán las medidas oportunas para asegurar que no perjudica ni al ser humano y ni al medio ambiente.

Purpose: Colorectal cancer is highly preventable by detecting and removing polyps, which are the precursors. Currently, the most accurate test is colonoscopy, but still misses 22% of polyps due to visualization limitations. In this paper, we preliminary assess the potential of microwave imaging and dielectric properties (e.g., complex permittivity) as a complementary method for detecting polyps and cancer tissue in the colon. The dielectric properties of biological tissues have been used in a wide variety of applications, including safety assessment of wireless technologies and design of medical diagnostic or therapeutic techniques (microwave imaging, hyperthermia, and ablation). The main purpose of this work is to measure the complex permittivity of different types of colon polyps, cancer, and normal mucosa in ex vivo human samples to study if the dielectric properties are appropriate for classification purposes. Methods: The complex permittivity of freshly excised healthy colon tissue, cancer, and histological samples of different types of polyps from 23 patients was characterized using an open-ended coaxial probe between 0.5 and 20 GHz. The obtained measurements were classified into five tissue groups before applying a data reduction step with a frequency dispersive single-pole Debye model. The classification was finally compared with pathological analysis of tissue samples, which is the gold standard. Results: The complex permittivity progressively increases as the tissue degenerates from normal to cancer. When comparing to the gold-standard histological tissue analysis, the sensitivity and specificity of the proposed method is the following: 100% and 95% for cancer diagnosis; 91% and 62% for adenomas with high-grade dysplasia; 100% and 61% for adenomas with low-grade dysplasia; and 100% and 74% for hyperplastic polyps, respectively. In addition, complex permittivity measurements were independent of the lesion shape and size, which is also an interesting property comparing to current colonoscopy techniques. Conclusions: The contrast in complex permittivities between normal and abnormal colon tissues presented here for the first time demonstrate the potential of these measurements for tissue classification. It also opens the door to the development of a microwave endoscopic device to complement the outcomes of colonoscopy with functional tissue information. This work was supported by the Department of Universitats, Recerca i Societat de la Informacio of the Catalan Government through Llavor 2014LLAV00016 and producte 2016PROD00068 projects, La Caixa through Caixaimpulse program CI16-00058, the Spanish Comision Interministerial de Ciencia y Tecnologıa (CICYT) under projects TEC2016- 78028-C3-1-P, TEC2014-58582-R, the Spanish Agencia Estatal de Investigacion Unidad de Excelencia Maria de Maeztu (MDM-2016-0600), the Spanish Ministerio de Economıa, Industria y Competitividad, DTS17/00090 and CERCA Programme/Generalitat de Catalunya.

©2017 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. Macrocells are expected to be densely overlaid by small cells (SCs) to meet increasing capacity demands. Due to their dense deployment, some SCs will not be connected directly to the core network, and thus, they may forward their traffic to the neighboring SCs until they reach it, thereby forming a multihop backhaul (BH) network. This is a promising solution, since the expected short length of BH links enables the use of millimeter-wave (mmWave) frequencies to provide high-capacity BH. In this context, user association becomes challenging due to the multihop BH architecture, and therefore, new optimal solutions should be developed. Thus, in this paper, we study the user association problem aiming at the joint maximization of network energy efficiency (EE) and spectrum efficiency (SE), without compromising the user quality of service (QoS). The problem is formulated as an e-constraint problem, which considers the transmit energy consumption both in the access network, i.e., the links between the users and their serving cells, and the BH links. The optimal Pareto-front solutions of the problem are analytically derived for different BH technologies, and insights are gained into the EE and SE tradeoff. The proposed optimal solutions, despite their high complexity, can be used as a benchmark for the performance evaluation of user association algorithms. We also propose a heuristic algorithm, which is compared with reference solutions under different traffic scenarios and BH technologies. Our results motivate the use of mmWave BH, whereas the proposed algorithm achieves near-optimal performance.

This is the peer reviewed version of the following article: A. M. Hagerstrom, X. Lu, N. M. Dawley, H. P. Nair, J. Mateu, R. D. Horansky, C. A. E. Little, J. C. Booth, C. J. Long, D. G. Schlom, N. D. Orloff, Adv. Mater. Technol. 2018, 3, 1800090. https://doi-org.recursos.biblioteca.upc.edu/10.1002/admt.201800090, which has been published in final form at https://doi.org/10.1002/admt.201800090. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Voltage-tunable dielectric materials are widely used for microwave-frequency signal processing. Among tunable dielectric thin films, (SrTiO3)nSrO Ruddlesden–Popper (RP) superlattices have exceptionally low loss at high frequencies. This paper reports the first realization of resonators, a ubiquitous building block of microwave components, fabricated on RP films, and an analysis of their static and dynamic tuning behavior. The RP film has a ferroelectric-paraelectric phase transition at ˜200 K, and the tunability is strongest at this temperature. The resonators have approximately 2.5% tuning of the resonance frequency at room temperature and 20% tuning at 200 K, and a tuning time scale of less than a nanosecond, which is limited by the measurement circuit rather than material properties.

©2018 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. Recently, a receive spatial modulation (RSM) for massive multiple-input-multiple-output operating in millimeter wave (mmWave) was introduced with the purpose of simplifying user terminal circuit by employing only one radio-frequency chain and attaining high spectral efficiency by exploiting the receive spatial dimension. However, when RSM is applied in a mmWave channel, it demands a challenging receive antenna selection (RAS) procedure. On the other hand, the power consumption at the transmitter side is high when a full digital (FD) precoder is envisioned. We consider the joint problem of RAS and precoder designs based low complexity hybrid architecture. For the sake of simplicity, we divide this problem into two subproblems. First, we design the RAS assuming FD precoder, and then, we design the hybrid precoder. We propose two novel and efficient RAS methods. First, we formulate the RAS as non-convex optimization problem. Then, we convert it into a convex optimization problem by introducing novel lower bounds and relaxing non-convex constraints. Second, we provide sequential algorithms that approach the optimal selection where we (add/remove) one (good/poor) antenna per iteration. We propose novel zero forcing hybrid precoder based convex optimization that maximizes the received power. We prove that the proposed precoder is optimal when the channel is highly spatially sparse. The proposed designs have been compared with the best known methods in terms of average mutual information and energy efficiency showing significant improvements.

El objetivo del TFG es la adición de tecnologíaRFID a un sistema de manipulación de cargas suspendidas (ganchos), con el objetivo de mejorar la trazabilidad en las operaciones con estas, y mejorar la seguridad mediante el control de mantenimiento preventivo delos elementos de amarre. Actualmente la empresa comercializa un sistema semiautomáticode manipulación de cargas suspendidas. El sistema actual se compone de dos elementos: un gancho automáticomotorizado, que cuando estácerca de la carga mediante un sistema de imanes es capaz de posicionarse correctamente; y un control remoto mediante el cual el usuario da la orden de cerrar el gancho para enganchar la carga y poder manipular-la.El proyecto considera la mejora del gancho actual, mediante la adición de un sistema electrónico que incorpore un lector de RFID que permita identificar la carga manipulada. Adicionalmente el sistema tendrá la capacidad de enviar hacia un servidor remoto las informaciones leídas mediante el lector RFID y recibir de éste consignas en cuanto a la seguridad en la manipulación de las cargas. 51.Introducción1.1.Objetivodel TFGEl objetivo del TFG es la adición de tecnologíaRFID a un sistema de manipulación de cargas suspendidas (ganchos), con el objetivo de mejorar la trazabilidad en las operaciones con estas, y mejorar la seguridad mediante el control de mantenimiento preventivo delos elementos de amarre. Actualmente la empresa comercializa un sistema semiautomáticode manipulación de cargas suspendidas. El sistema actual se compone de dos elementos: un gancho automáticomotorizado, que cuando estácerca de la carga mediante un sistema de imanes es capaz de posicionarse correctamente; y un control remoto mediante el cual el usuario da la orden de cerrar el gancho para enganchar la carga y poder manipular-la.El proyecto considera la mejora del gancho actual, mediante la adición de un sistema electrónico que incorpore un lector de RFID que permita identificar la carga manipulada. Adicionalmente el sistema tendrá la capacidad de enviar hacia un servidor remoto las informaciones leídas mediante el lector RFID y recibir de éste consignas en cuanto a la seguridad en la manipulación de las cargas.Figura 1: Concepto del PFGEn el grafico podemos ver un diagrama con los elementos que conforman el sistema actual (gancho y control remoto) y los elementos que se pretende añadir al sistema: un lector RFID en el gancho, y un micro-ordenador que funcione como pasarela hacia la red.Mediante la inclusión de RFID se pretende dotar al sistema de funciones de trazabilidad, así como ser capaz en un futuro a corto plazo de mejorar el mantenimiento preventivo y predictivo de las eslingas, mediante el control del histórico de operaciones de cada eslinga. Se pretende que el sistema sea capaz en un futuro próximo de detectar las eslingas que han sido sometidas a sobreesfuerzos y deshabilitarlas de manera remota.

©2017 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. This paper presents a phenomenological equivalent circuit to model the phenomenon occurring when a section of superconducting transmission line transits from a superconducting state to a normal state. This phenomenon allows the use of superconductors for the design of autolimiting structures based on superconducting transmission line sections. Although this autolimiting effect happens when the current density achieved in the superconductor exceeds the critical current inherent to the superconducting material, heating effects also play a significant role in this behavior. The equivalent circuit presented in this work accounts for both electric and thermal effects, and the interaction between them. The circuit model is then used for the evaluation of a practical microwave and frequency selective IMUX configuration.

MERITXELL is a ground-based multisensor instrument that includes a multiband dual-polarization radiometer, a GNSS reflectometer, and several optical sensors. Its main goals are twofold: to test data fusion techniques, and to develop Radio-Frequency Interference (RFI) detection, localization and mitigation techniques. The former is necessary to retrieve complementary data useful to develop geophysical models with improved accuracy, whereas the latter aims at solving one of the most important problems of microwave radiometry. This paper describes the hardware design, the instrument control architecture, the calibration of the radiometer, and several captures of RFI signals taken with MERITXELL in urban environment. The multiband radiometer has a dual linear polarization total-power radiometer topology, and it covers the L-, S-, C-, X-, K-, Ka-, and W-band. Its back-end stage is based on a spectrum analyzer structure which allows to perform real-time signal processing, while the rest of the sensors are controlled by a host computer where the off-line processing takes place. The calibration of the radiometer is performed using the hot-cold load procedure, together with the tipping curves technique in the case of the five upper frequency bands. Finally, some captures of RFI signals are shown for most of the radiometric bands under analysis, which evidence the problem of RFI in microwave radiometry, and the limitations they impose in external calibration.

©2017 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. Radio–frequency interference (RFI) signals are a well-known threat for microwave radiometry (MWR) applications. In order to alleviate this problem, different approaches for RFI detection and mitigation are currently under development. Since RFI signals are man made, they tend to have their power more concentrated in the time–frequency (TF) space as compared to naturally emitted noise. The aim of this paper is to perform an assessment of different TF RFI mitigation techniques in terms of probability of detection, resolution loss (RL), and mitigation performance. In this assessment, six different kinds of RFI signals have been considered: a glitch, a burst of pulses, a wide-band chirp, a narrow-band chirp, a continuous wave, and a wide-band modulation. The results show that the best performance occurs when the transform basis has a similar shape as compared to the RFI signal. For the best case performance, the maximum residual RFI temperature is 14.8 K, and the worst RL is 8.4%. Moreover, the multiresolution Fourier transform technique appears as a good tradeoff solution among all other techniques since it can mitigate all RFI signals under evaluation with a maximum residual RFI temperature of 21 K, and a worst RL of 26.3%. Although the obtained results are still far from an acceptable bias Misplaced < 1 K for MWR applications, there is still work to do in a combined test using the information gathered simultaneously by all mitigation techniques, which could improve the overall performance of RFI mitigation.

The demonstration of the feasibility of navigation signals signals for remote sensing has lead to a significant increase of new GNSS-R instruments in the recent years. Despite of the type instrument, the observables are based on the cross-correlations of the received GNSS signals. Most of these instruments combine the signals received by multiple chains, in such a way that they need a proper calibration. This work proposes a calibration procedure for GNSS-R instruments by using a calibration signal with similar statistics to the GNSS signals. The method is tested and validated with the Microwave Interferometric Reflectometer (MIR) instrument, which contains 152 chains. The test results will be presented at the conference.

This project presents a Doherty amplifier design and implementation based on two commercial microwave amplifiers. Its purpose is efficiency improvement for low power levels, between 0 and 6 dBm, and cost reduction with respect to discrete transistor amplifier design and fabrication. Microstrip technology has been chosen for this design realization because of the easy/simple fabrication process, possibility of SMD devices integration and transmission lines adjustment ("tuning"). During the design process ADS designing tool has been used. Duroid 4003C has been chosen as substrate with 0.81 mm of thickness and copper as conductor with 17.5 ?m thickness. The operating frequency is 1.8 GHz as it belongs to the mobile frequency band. Parameters X were used in the design process and non-linear modeling was developed by experimental measurements with Vector Network Analyser and Spectrum Analyser. En aquest projecte es presenta el disseny i implementació d'un amplificador Doherty, amb el propòsit d'augmentar l'eficiència per potències d'entrada més baixes, de 0 a 6 dBm, realitzat a partir de dos amplificadors comercials de microones, amb l'objectiu de disminuir el cost que implica el disseny dels amplificadors amb transistors discrets i la fabricació. Per a la realització d'aquest disseny s'ha escollit la tecnologia microstrip, degut a la facilitat de fabricació, la col·locació dels dispositius SMD i l'ajust de les línies ("tuning"). Durant el disseny s'ha utilitzat l'eina ADS (Advanced Design System 2014.01). El substrat i el conductor que s'han utilitzat són duroid 4003C amb una alçada de 0.81 mm i el coure amb un gruix de 17.5 m, respectivament. La freqüència de treball escollida es de 1.8 GHz, ja que pertany a la banda de freqüències de telefonia mòbil cel·lular. S'han utilitzat els paràmetres X per al disseny i s'ha desenvolupat una modelació no lineal a partir de mesures experimentals amb l'analitzador de xarxes vectorial i l'analitzador d'espectres. Este proyecto presenta el diseño e implementación de un amplificador Doherty, cuyo propósito es aumentar la eficiencia para potencias de entrada bajas, de 0 a 6 dBm de potencia de entrada, realizado a partir de dos amplificadores comerciales de microondas, con el objetivo de disminuir el coste que conlleva el diseño con transistores discretos y la fabricación del amplificador. Para la realización de este diseño se ha escogido la tecnología microstrip, debido a la facilidad de fabricación, colocación de dispositivos SMD y ajuste de las líneas ("tuning"). Durante el diseño se ha utilizado la herramienta ADS. El sustrato elegido es duroid 4003C con un espesor de 0.81 mm y el conductor es cobre con un espesor de 17.5 m. La frecuencia de trabajo escogida es de 1.8 GHz, dado que pertenece a la banda de frecuencias de telefonía móvil celular. Se han utilizado los parámetros X para el diseño y se ha desarrollado un modelado no lineal a partir de medidas experimentales con el analizador de redes y el analizador de espectros.

Las variaciones en la actividad solar afectan a la ionosfera.La monitorización de señales de radio VLF(Very Low Frequency) permite obtener información relevante sobre la actividad solar. Se propone diseñar y construir receptores de radio basados en tecnologías SDR (Software Defined Radio) y experimentar con diferentes antenas The aim of this project is to design and build a station which can detect certain phenomena taking place in the sun. In order to make it possible, the electromagnetic waves amplitude received in the VLF band (Very Low Frequency) is monitored under assumption that these phenomena (solar flares), cause changes in the D layer of the ionosphere playing an important role in the propagation of waves in the VLF band, and therefore, the received amplitude of these waves will be disturbed. The methodology used in this project involved a deep study of the propagation of the electromagnetic waves in this frequency band, its characteristics and stations broadcasting in this band. Then, all stages of the station has been designed and built beginning with the antenna which will capture the tension of a radio station in the VLF band, until the last stage whose function would be to detect the amplitude of the voltage and monitor it to detect those changes caused by solar activity. Finally, the amplitude of the radio station DHO38 was monitored and the results have been contrasted with data obtained through the satellite GOES15 belonging to the National Oceanic and Atmospheric Administration (NOAA) of the United States. These results prove that the receiver which has been designed work properly and it enables to scientists who study these issues to have an effective and inexpensive platform to monitor solar activity, or as recent studies suggest, early detection of seismic events. El objetivo de este proyecto es diseñar y construir una estación capaz de detectar ciertos fenómenos que tienen lugar en el sol. Para llevarlo a cabo, se monitoriza la amplitud con la que se reciben las ondas electromagnéticas en la banda (Very Low Frequency – VLF), bajo hipótesis de que estos fenómenos (erupciones solares), provocan alteraciones en la capa D de la ionosfera que juega un papel importante en la propagación de las ondas en la banda VLF, y por lo tanto, se alterará la amplitud recibida de estas ondas. La metodología seguida en este proyecto ha consistido en estudiar bien la propagación de las ondas electromagnéticas en esta banda frecuencial, sus características y las emisoras que emiten en esta banda. A continuación, se han diseñado y construido todas las etapas de la estación empezando por la antena que se encargará de capturar la tensión de una emisora en la banda VLF, hasta la última etapa cuya función sería de detectar la amplitud de dicha tensión y monitorizarla para detectar aquellas alteraciones provocadas por la actividad solar. Finalmente, se ha monitorizado la amplitud correspondiente a la emisora DHO38 y los resultados obtenidos han sido contrastados con los datos obtenidos a través del satélite GOES15 que pertenece a la Administración Nacional Oceánica y Atmosférica (NOAA) de los Estados Unidos. Estos resultados prueban que el receptor que se ha diseñado funciona correctamente posibilitando a los científicos que estudian estos temas disponer de una plataforma eficaz y barata para monitorizar la actividad solar, o incluso como apuntan recientes estudios, detectar anticipadamente fenómenos sísmicos. L'objectiu d'aquest projecte és dissenyar i construir una estació capaç de detectar certs fenòmens que tenen lloc al sol. Per fer-ho, es monitoritza l'amplitud amb què es reben les ones electromagnètiques en la banda (Very Low Frequency - VLF), sota hipòtesi que aquests fenòmens (erupcions solars), provoquen alteracions en la capa D de la ionosfera que té un paper important en la propagació de les ones a la banda VLF, i per tant, s'alterarà l'amplitud rebuda d'aquestes ones. La metodologia seguida en aquest projecte ha consistit en estudiar bé la propagació de les ones electromagnètiques en aquesta banda freqüencial , les seves característiques i les emissores que emeten en aquesta banda. A continuació, s'han dissenyat i construït totes les etapes de l'estació començant per l'antena que s'encarregarà de capturar la tensió d'una emissora a la banda VLF, fins a l'última etapa que la seva funció seria detectar l'amplitud d'aquesta tensió i monitoritzar-la per detectar aquelles alteracions provocades per l'activitat solar. Finalment, s'ha monitoritzat l'amplitud corresponent a l'emissora DHO38 i els resultats obtinguts han estat contrastats amb les dades obtingudes a través del satèl·lit GOES15 que pertany a l'Administració Nacional Oceànica i Atmosfèrica (NOAA) dels Estats Units. Aquests resultats proven que el receptor que s'ha dissenyat funciona correctament possibilitant als científics que estudien aquests temes disposar d'una plataforma eficaç i barata per monitoritzar l'activitat solar, o fins i tot com apunten recents estudis, detectar anticipadament fenòmens sísmics.

The chipless RFID tag presented in this thesis is based in the millimetre wave technology and exploits the advantage offered by the polarization and frequency diversity for detecting and identifying. The RFID tag and reader consist on a ring slot etched on the top of a circular Substrate Integrated Waveguide (SIW) cavity. Adding a gap as a shot in the ring slot, it is possible to detect different linear polarization depending of the angle position of the gap. Moreover, a new system of identification of the vital signal detection is proposed using RFID technology. The detection is based in different circular polarization tags located in the chest of different individuals. The received signal power corresponding to the chest vibration is analysed in order to compare the response of different tags. Use of this type of technology allows identifying different individual and monitoring their vital signal with a small, compact and low cost system based in the millimetre wave frequency. En esta tesis se presenta un Sistema RFID pasivo basado en tecnología de ondas milimétricas que explota la ventaja que ofrece la diversidad de polarización y frecuencia para detectar e identificar. La etiqueta y el lector RFID consisten en una ranura en forma de anillo grabada en la parte superior de una cavidad circular diseñada con tecnología de guía de onda integrada en sustrato. Añadiendo un hueco causando un cortocircuito en el anillo es posible detectar diferentes tipos de polarización lineal dependiendo de la posición del hueco. Además, se propone un nuevo sistema de detección de las señales vitales usando tecnología RFID. La detección se basa en diferentes etiquetas RFID colocadas en el pecho de diferentes individuos. La señal recibida correspondiente a la vibración del pecho es analizada comparando distintas respuestas de distintas etiquetas. El uso de este tipo de tecnología permite identificar distintos individuos monitorizando sus señales vitales con un sistema pequeño, compacto y barato basado en frecuencias de ondas milimétricas. En aquesta tesi es presenta un Sistema RFID passiu basat en tecnologia d'ones mil·limètriques que explota l'avantatge que ofereix la diversitat de polarització i freqüència per detectar i identificar. L'etiqueta i el lector RFID consisteixen en una ranura en forma d'anell gravada a la part superior d'una cavitat circular dissenyada amb tecnologia de guia d'ona integrada en substrat. Afegint una ranura causant un curtcircuit en l'anell és possible detectar diferents tipus de polarització lineal depenent de la posició de la ranura. A més, es proposa un nou sistema de detecció del senyal vital usant tecnologia RFID. La detecció es basa en diferents etiquetes RFID col·locades al pit de diferents individus. La senyal rebuda corresponent a la vibració del pit és analitzada comparant diferents respostes de diferents etiquetes. L'ús d'aquest tipus de tecnologia permet identificar diferents individus monitoritzant els seus senyals vitals amb un sistema petit, compacte i barat basat en freqüències d'ones mil·limètriques.

This paper presents a phenomenological equivalent circuit to model the phenomenon occurring when a section of superconducting transmission line transits from a superconducting state to a normal state. This phenomenon allows the use of superconductors for the design of autolimiting structures based on superconducting transmission line sections. Although this autolimiting effect happens when the current density achieved in the superconductor exceeds the critical current inherent to the superconducting material, heating effects also play a significant role in this behavior. The equivalent circuit presented in this work accounts for both electric and thermal effects, and the interaction between them. The circuit model is then used for the evaluation of a practical microwave and frequency selective IMUX configuration.

The European Space Agency's Soil Moisture and Ocean Salinity (SMOS) mission has been providing L-band brightness temperature (BT) using its instrument, the Microwave Imaging Radiometer using Aperture Synthesis. In the measurements, the negative effect of radio frequency interference (RFI) is clearly present, deteriorating the quality of geophysical parameter retrieval. Detection and geolocation of RFI sources are essential to remove or at least mitigate the RFI impacts and ultimately improve the performance of parameter retrieval. This paper discusses a new approach to SMOS RFI source detection, based on the MUltiple SIgnal Classification (MUSIC) algorithm. Recently, the feasibility of MUSIC direction-of-arrival estimation has been shown for the RFI source detection of the synthetic aperture interferometric radiometer. This paper refines the MUSIC RFI source detection algorithm and tailors it to the SMOS scenario. To consolidate the RFI source detection procedure, several required steps are devised, including the rank estimation of the covariance matrix, local peak detection and thresholds, and multiple-snapshot processing. The developed method is tested using a number of SMOS visibility samples. In the test results, the MUSIC method shows an improvement on the accuracy and precision of the RFI source geolocation, compared with a simple detection method based on the local peaks of BT images. The MUSIC results especially outperform the SMOS BT image on the spatial resolution

© 2016 [2016 Optical Society of America.]. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited. To simulate in the laboratory the influence that a turbulent atmosphere has on light beams, we introduce a practical method for generating atmospheric wavefront distortions that considers digital holographic reconstruction using a programmable binary micromirror array. We analyze the efficiency of the approach for different configurations of the micromirror array and experimentally demonstrate the benchtop technique. Though the mirrors on the digital array can only be positioned in one of two states, we show that the holographic technique can be used to devise a wide variety of atmospheric wavefront aberrations in a controllable and predictable way for a fraction of the cost of phase-only spatial light modulators.

There are two important considerations in the development of an electrical model for RF cavities to be used for system analysis or LLRF loop design, being: transient response and cavity impedance mismatch. In the literature, however, either one or both of these issues are often neglected depending whether the RF cavity is being looked at from high-power or low-level RF perspectives. In this work, a transient model for storage ring RF cavities under beam loading is developed so that it represents the important RF aspects of the cavity such as impedance mismatch and reflected voltage as well as its transient response, for example at start-up or upon beam arrival. As a special case, the model is applied to the RF cavity of the ALBA storage ring to study the effects arising from beam loading, system start-up and delays on the performance of the LLRF regulation loops. For the simulation of the regulation loops in time domain a mathematical technique is introduced to map the RF frequency to baseband, leading to the baseband-equivalent model of the cavity with almost the same results as the conventional cavity model but with significantly higher simulation speed.

The performance of microwave radiometers can be seriously degraded by the presence of radio-frequency interference (RFI). Spurious signals and harmonics from lower frequency bands, spread-spectrum signals overlapping the “protected” band of operation, or out-of-band emissions not properly rejected by the pre-detection filters due to the finite rejection modify the detected power and the estimated antenna temperature from which the geophysical parameters will be retrieved. In recent years, techniques to detect the presence of RFI have been developed. They include time- and/or frequency domain analyses, or statistical analysis of the received signal which, in the absence of RFI, must be a zero-mean Gaussian process. Current mitigation techniques are mostly based on blanking in the time and/or frequency domains where RFI has been detected. However, in some geographical areas, RFI is so persistent in time that is not possible to acquire RFI-free radiometric data. In other applications such as sea surface salinity retrieval, where the sensitivity of the brightness temperature to salinity is weak, small amounts of RFI are also very difficult to detect and mitigate. In this work a wavelet-based technique is proposed to mitigate RFI (cancel RFI as much as possible). The interfering signal is estimated by using the powerful denoising capabilities of the wavelet transform. The estimated RFI signal is then subtracted from the received signal and a “cleaned” noise signal is obtained, from which the power is estimated later. The algorithm performance as a function of the threshold type, and the threshold selection method, the decomposition level, the wavelet type and the interferenceto-noise ratio is presented. Computational requirements are evaluated in terms of quantization levels, number of operations, memory requirements (sequence length). Even though they are high for today’s technology, the algorithms presented can be applied to recorded data. The results show that even RFI much larger than the noise signal can be very effectively mitigated, well below the noise level.

Accurate localization of microwave emitting sources is an important topic, in telecommunication and remote sensing. Especially, in order to increase the data quality of satellite microwave remote sensing, radio frequency interference (RFI) sources need to be accurately geolocated. This project offers the opportunity to learn and experience the method for high-performance detection and localization of RFI sources. Study of radio frequency interference definition and detection techniques. Estudio de la definición de interferencias en las bandas de radiofreqüència y técnicas para su detección. Estudi de la definició de interferències en bandes de radiofreqüència i técniques per la seva detecció.

We explore a new wavelength management for ultradense wavelength division multiplexing- passive optical network with randomly distributed optical network unit (ONU) wavelengths, controlled with limited thermal tunability. Static and dynamic wavelength assignment paradigms and heuristic assignment schemes for spectrum management are proposed, simulated, and compared. ONU acceptances in activation processes and ONU availability ratios up to 99.99% are obtained in standard environmental conditions.

This Thesis will apply the multimodal theory to the design of microwave band-pass filters that will be implemented in uniplanar CPW technology. The work proposed on this master thesis has its background in the multimodal theory, in which coplanar waveguides structures propagate more than one fundamental mode: the even and the odd mode, and it’s the iteration between these two modes that allows to achieve this new circuit concept. Since this is a relative new technology there are not many filter proposals and the focus of this MT is the development of low-loss and selective bandpass filters. During this work multimodal filters showed a very good response and made possible to create very compact designs that could be implemented in small devices. Furthermore these types of filter presented a way of rejecting harmonic frequencies, making them offer a good response over a wide band of frequencies.

5 pages, 3 figures, 2 tables.-- © 2015 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., Radio-frequency interference (RFI) seriously affects the retrieval of geophysical parameters from the measurements of microwave radiometers. An accurate geolocation of the RFI is crucial to effectively switch off illegal transmitters. In this letter, a new RFI localization method is proposed to improve the achievable angular resolution by using beamforming and direction-of-arrival (DOA) estimation techniques. The proposed RFI localization techniques can be employed in synthetic aperture interferometric radiometers, such as the European Space Agency (ESA) Soil Moisture and Ocean Salinity (SMOS) mission. Two DOA estimation techniques are tested for the RFI localization: Capon and MUSIC. The feasibility of these methods is demonstrated with SMOS data. In the test results, the MUSIC beamforming shows a better performance of RFI localization than the SMOS Fourier imaging and the Capon, in terms of accuracy and resolution. © 2014 IEEE

La idea de este proyecto de final de carrera ha sido estudiar la viabilidad de la implantación de la tecnología RFID en la fase de etiquetado y alarmado de prendas de ropa en la empresa Philpark. La actividad de la empresa es la comercialización de prendas de vestir de estilo urbano. En primer lugar, se presenta la empresa Philpark, haciendo un recorrido por la historia de la marca, desde sus inicios en 2008 hasta la actualidad. Se hace hincapié en la visión de la empresa y se analiza el modelo de negocio que sigue, comparándolo con los modelos de negocio de las grandes empresas del sector. Seguidamente, se analiza el sector en el que opera la marca y se identifican sus principales competidores dentro del sector. Esta descripción general de la empresa es útil para entender, posteriormente, el análisis económico que se realiza de la marca. Se pretende observar el gran crecimiento de la empresa y comprobar si se encuentra en situación de afrontar la implantación. Se presenta la tecnología usada en el proceso de etiquetado actual, el código de barras. A continuación, se analiza el sistema logístico vigente entendiendo qué se realiza en cada fase del proceso y se calculan los costes existentes en el proceso. En segundo lugar, se investiga sobre la tecnología RFID: cómo funciona, qué elementos son requeridos y qué características la hacen una tecnología puntera que utilizan empresas multinacionales importantes en el sector del retail. Previamente, se justifica su implantación frente a otras tecnologías. A continuación, se valoran los distintos escenarios en los que implantar la tecnología por radio frecuencia. Se elige el tipo de tag, luego se analiza donde colocar el tag y finalmente, dónde producirlo y codificarlo. Con toda esta información recogida, se realiza un estudio económico de la inversión a cuatro años vista. El estudio se divide en dos fases: primeramente, se estudiará una primera inversión en la que se tendrá en cuenta la implantación en las tiendas actuales (sin expansión). En caso de ser favorable, se analizará la inversión con la previsión de aperturas de tiendas propias de la compañía. Finalmente, se realiza un estudio presupuestario del proyecto. Para acabar, se estudia el impacto medioambiental del proyecto para observar la afectación del proyecto en el medio.

Nowadays the RFID technology is being used in more technological. Industries, medicine, transport, sport and package delivery are a few examples of the business sectors that use this technological invention.This project describes the development and implementation process of a software application that controls a specific UHF RFID reader. The initial section represent the RFID technology context, giving a general vision of applications, standards and its components. Then, the project introduces in a more specific way the different blocks that compose the application. The code and application structure are exposed in detail. The last section shows the measures performed and the obtained results by doing a RFID tag behaviour study demonst rating the correct application and tag’s performance. Actualment la utilització de la tecnologia RFID està en augment i c ada cop són més els camps d’aplicació. La indústria, la medicina, el transport, l’esport , el control d’inv entari i l’enviament de paquets són alguns exemples de sectors que utilitzen aquesta tecnologia d’auto - identificació. Aquest projecte descriu el desenvolupament i la implementació d’un programa software de cont rol d’un lector UHF RFID específic. En els ap artats inicials s’exposa el context de la tecnologia RFID donant una visió general de les aplicacions, estàndards i elements que la composen. Posteriorment s’ introdueix de manera més específica els blocs i classes de l’aplicació realitzada , es parla del co di i de l’estructura de l’aplicació . Per últim , s’exposen les mesures realitzades així com els resultats obtinguts al fer un estudi sobre el comportament de les etiquetes RFID, mostrant que l’aplicació funciona i que el tag en diferents posicions i ambient s varia.

©2014 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. In this letter, a practical fabrication of a novel inhomogeneous gradient-index dielectric flat lens for millimeter-wave applications is presented. A previous theoretical design of a dielectric flat lens composed of different permittivity materials is now modeled and analyzed for a practical prototype fabrication and performance evaluation at 60 and 77 GHz. The measurement results at 60 GHz show that with the novel gradient-index dielectric flat lens antenna prototype, we can achieve up to 18.3 dB of broadside gain, beam-steering capabilities in both planes from -30 degrees to +30 degrees with around 15 dB of gain, and up to +/- 45 degrees with around 14 dB of gain, with low sidelobe levels. At 77 GHz, the performance evaluation shows that we can obtain up to 18.9 dB of broadside gain, beam-steering capabilities in both planes from -30 degrees to +30 degrees with around 17 dB of gain and low sidelobe levels, and up to +/- 45 degrees with around 15 dB of gain. This novel design leads to a low-cost, low-profile, and lightweight antenna solution, easy to integrate in a compact millimeter-wave wireless communication system.

This paper presents the theory, design procedure, and implementation of a dual-band planar quadrature hybrid with enhanced bandwidth. The topology of the circuit is a three-branch-line (3-BL) quadrature hybrid, which provides much larger flexibility to allocate the desired operating frequencies and necessary bandwidths than other previously published configurations. A performance comparison with other dual-band planar topologies is presented. Finally, a 3-BL quadrature hybrid for dual band (2.4 and 5 GHz) wireless local area network systems was fabricated, aimed to cover the bands corresponding to the standards IEEE802.11a/b. The measurements show a 16% and 18% bandwidth for the lower and upper frequency, respectively, satisfying and exceeding the bandwidth requirements for the above standards.

Microwave tomography is proposed for medical diagnosis using Magnitude Combined tomographic algorithm. A proof-of-concept experimental system was build and an in-homogeneous breast phantom with a tumor embedded was successfully reconstructed in less than 30 seconds per frequency. The motivation for this study is the future development of an imaging prototype for head imaging.

Sensors in the range of visible and near-shortwave-thermal infrared regions can be used in combination with passive microwave observations to provide soil moisture maps at much higher spatial resolution than the original resolution of current radiometers. To do so, a new downscaling algorithm ultimately based on the land surface temperature (LST) - Normalized Difference Vegetation Index (NDVI) - Brightness Temperature (T-B) relationship is used, in which shortwave infrared indices are used as vegetation descriptors, instead of the more common near infrared ones. The theoretical basis of those indices, calculated as the normalized ratio of the 1240, 1640 and 2130 nm shortwave infrared (SWIR) bands and the 858 nm near infrared (NIR) band indicate that they are able to provide estimates of the vegetation water content. These so-called water indices extracted from MODIS products, have been used together with MODIS LST, and SMOS T-B to improve the spatial resolution of similar to 40 km SMOS soil moisture estimates. The aim was to retrieve soil moisture maps with the same accuracy as SMOS, but at the same resolution of the MODIS dataset, i.e., 500 m, which were then compared against in situ measurements from the REMEDHUS network in Spain. Results using two years of SMOS and MODIS data showed a similar performance for the four indices, with slightly better results when using the index derived from the first SWIR band. For the areal-average, a coefficient of correlation (R) of similar to 0.61 and similar to 0.72 for the morning and afternoon orbits, respectively, and a centered root mean square difference (cRMSD) of similar to 0.04 m(3) m(-3) for both orbits was obtained. A twofold improvement of the current versions of this downscaling approach has been achieved by using more frequent and higher spatial resolution water indexes as vegetation descriptors: (1) the spatial resolution of the resulting soil moisture maps can be enhanced from similar to 40 km up to 500 m, and (2) more accurate soil moisture maps (in terms of R and cRMSD) can be obtained, especially in periods of high vegetation activity. The results of this study support the use of high resolution LST and SWIR-based vegetation indices to disaggregate SMOS observations down to 500 m soil moisture maps, meeting the needs of fine-scale hydrological applications.

Simple functions of radar backscatter coefficients have been proposed as indices of soil moisture and vegetation, such as the radar vegetation index, i.e., RVI, and the soil saturation index, i.e., m(s). These indices are ratios of noisy and potentially miscalibrated radar measurements and are therefore particularly susceptible to estimation errors. In this study, we consider uncertainty in satellite estimates of RVI and m(s) arising from two radar error sources: noise and miscalibration. We derive expressions for the variance and bias in estimates of RVI and m(s) due to noise. We also derive expressions for the sensitivity of RVI and m(s) to calibration errors. We use one year (September 1, 2011 to August 31, 2012) of Aquarius scatterometer observations at three polarizations (sigma(HH), sigma(VV), and sigma(HV)) to map predicted error estimates globally, using parameters relevant to the National Aeronautics and Space Administration Soil Moisture Active and Passive satellite mission. We find that RVI is particularly vulnerable to errors in the calibration offset term over lightly vegetated regions, resulting in overestimates of RVI in some arid regions. m(s) is most sensitive to calibration errors over regions where the dynamic range of the backscatter coefficient is small, including deserts and forests. Noise induces biases in both indices, but they are negligible in both cases; however, it also induces variance, which is large for highly vegetated regions (for RVI) and areas with low dynamic range in backscatter values (for m(s)). We find that, with appropriate temporal and spatial averaging, noise errors in both indices can be reduced to acceptable levels. Areas sensitive to calibration errors will require masking.

Estudi i anàlisi d'estructures "SLOW WAVE" amb tecnologia coplanar i comparació entre estructures. [ANGLÈS] Study and analysis of different slow wave structures designed with coplanar technology and subsequent comparative between these structures from experimental results. [CASTELLÀ] Estudio y análisis de diferentes estructuras slow wave diseñadas con tecnología coplanar y posterior comparativa entre estructuras a partir de resultados experimentales. [CATALÀ] Estudi i anàlisi de diferents estructures slow wave dissenyades amb tecnologia coplanar i posterior comparativa entre estructures a partir de resultats experimentals.

Treball realitzat a la Beihang University of Aeronautics and Astronautics [ANGLÈS] This work is part of ongoing research conducted at Beihang University relating to signal generating. The primary objective of this thesis was to develop a flexible, high-performance Radio Frequency (RF) generator platform in order to facilitate research on channel response. A FPGA-based system architecture utilizing a stacked, multi-board design was created to meet this goal. A combination of a Liquid-Crystal Display (LCD), power supply, FPGA control and RF generator were employed in the new system. [CASTELLÀ] Este trabajo es parte de la investigación en curso llevado a cabo en la Universidad de Beihang en el departamento de Teoría de señal. El objetivo principal de esta tesis es el desarrollo de una plataforma flexible y de alto rendimiento para un generador de radiofrecuencia (RF) con el objetivo de facilitar el estudio en los canales de comunicación. Una arquitectura de sistema basado en FPGA utilizando un diseño multi-placa de apilamiento fue creado para cumplir con este objetivo. Una combinación de una pantalla de cristal líquido (LCD), fuente de alimentación, control FPGA y el generador de RF fueron empleados en el nuevo sistema. [CATALÀ] Aquest treball és part de la investigació en curs dut a terme a la Universitat de Beihang en el departament de Teoria del senyal. L'objectiu principal d'aquesta tesi es el desenvolupament duna plataforma flexible i de alt rendiment per una generador de radiofreqüència (RF) amb l’objectiu de facilitar l’estudi en els canals de comunicació. Una arquitectura de sistema basat en FPGA utilitzant un disseny multi-placa d'apilament va ser creat per complir amb aquest objectiu. Una combinació d'una pantalla de cristall líquid (LCD), font d'alimentació, control FPGA i el generador de RF van ser emprats en el nou sistema.

Este proyecto se basa en la programación y diseño de un sistema que monitorice la temperatura de diversos puntos que pueden estar alejados entre sí y se visualicen dichas temperaturas en un punto central con conexión inalámbrica entre sensores y pantalla. Primero de todo ha sido necesario diseñar la estructura del sistema y definir las especificaciones, como el número de sensores, la manera en que se organizará el intercambio de información y cómo el usuario podrá manejar el sistema. Para que la unidad central se pueda comunicar con todos los sensores sin que aparezcan interferencias se ha multiplexado el tiempo. Es decir, se ha dividido el ciclo de funcionamiento del sistema en diversos espacios de tiempo en el cual en cada uno de ellos se comunicará uno de los sensores con la unidad central. Posteriormente se han analizado los requisitos de ambas unidades y se ha definido el medio de transmisión de información como ondas de radiofrecuencia. También se han definido el microcontrolador a utilizar y los módulos que contendrán dichas unidades. Con los módulos definidos se han escogido la marca y el modelo de cada componente. PIC18F4520 como microcontrolador, DS18B20 como sensor de temperatura, LCD1602 como pantalla y nRF24L01 como módulo de radiofrecuencia. La elección se ha basado principalmente por su alta disponibilidad en la universidad. Con el sistema totalmente definido ha sido necesario programar ambas unidades de modo que la primera lea la temperatura y la envíe a la unidad central para que la procese cuando ésta le indique, guarde las máximas y mínimas de cada sensor y las visualice por la pantalla. Para la programación de ambas unidades ha sido necesario utilizar subrutinas previamente creadas para los diversos componentes del sistema. Es conveniente recalcar que durante la programación han surgido diversos contratiempos como el que la pantalla compartiese puertos con el modulo de radiofrecuencia y haya sido necesario multiplexar la señal y deshabilitar cada componente cuando el otro es el que está siendo usado. Otro inconveniente importante ha sido el de los botones, éstos utilizan unos registros por defecto que ya eran utilizados por la pantalla y han sido necesario utilizar otros y conectarlos mediante cables. Además ha sido necesario controlar los rebotes de dichos botones. Por último se han calculado las prestaciones finales del sistema, éstas son el consumo, el alcance, el rango de temperaturas, la alimentación, el coste y el impacto medioambiental.

We demonstrate a simple fast method of laser wavelength channel switching for the wavelength management of UDWDM-PONs where the ONUs have source wavelengths with random distribution and are controlled with limited thermal tunability.