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Este Objeto de Aprendizaje (OA) permite calcular la atenuación por lluvia excedida en el 0.01% del tiempo de acuerdo a la Rec. ITU-R P.838.

Este Objeto de Aprendizaje (OA) representa el coeficiente de difracción, en módulo y fase, para un obstáculo agudo, proporcionando su valor para una situación especifica.

Este Objeto de Aprendizaje (OA) permite simular el ancho de banda necesario para garantizar una determinada velocidad de trasmisión en un radioenlace digital.

Este Objeto de Aprendizaje (OA) permite simular las pérdidas de propagación para un modelo a una pendiente (One Slope Model, OSM) en un margen de distancias Tx-Rx dado y para los parámetros del modelo definidos por el usuario (término de offset, exponente de pérdidas y shadow factor). Este modelo establece una relación lineal entre las pérdidas en dB y el logaritmo de la distancia.

Este Objeto de Aprendizaje (OA) permite calcular la capacidad ergodica de un sistema MIMO en función de la relación SNR para un canal radio con estadística Rayleigh.

Este ibjeto de aprendizaje permite simular las pérdidas de propagación para un modelo donde se establece una relación lineal entre el logaritmo de la pérdidas y la distancia (Linear Slope Model, LSM) en un margen de distancias Tx-Rx dado y para los parámetros del modelo definidos por el usuario (término de offset, exponente de pérdidas y shadow factor). Este tipo de modelo está más orientado a escenarios de interiores.

Este objeto de aprendizaje muestra las prestaciones de un sistema en diversidad cuando se utiliza una técnica de combinación por selección (SC, Selection Combining). El usuario puede indicar el número de ramas en diversidad, asumiendo un comportamiento totalmente incorrelado entre las diferentes señales recibidas, y la desviación típica (sigma) que indica la variabilidad temporal de la señal.

[ES] En este Trabajo Final de Grado se ha realizado una caracterización teórica y experimental del canal radio en las bandas definidas en el despliegue del estándar de comunicaciones 5G en ondas milimétricas. Para ello, se parte de una campaña de medidas que permite obtener la respuesta impulsional del canal a partir de la cual se derivan sus parámetros característicos de dispersión temporal (delay spread) y ancho de banda de coherencia. Las medidas se realizaron en el dominio de la frecuencia en la banda de 25 a 40 GHz. A partir del análisis de las medidas, se ha realizado la clusterización del PDP (Power Delay Profile) permitiendo así agrupar las distintas contribuciones multicamino con retardos y amplitudes similares. Finalmente, tras la clusterización, se ha parametrizado el PDP tomando como referencia el modelo de Saleh­-Valenzuela., [EN] In this Final Degree Project, a theoretical and experimental characterization of the radio channel has been carried out in the bands defined in the deployment of the 5G communications standard in millimeter waves. In order to do this, a measurement campaign was provided, where the impulse response of the channel was obtained. From the impulse response, its characteristic parameters of temporal dispersion (delay spread) and coherence bandwidth are derived. The measurements were made in the frequency domain in the band from 25 to 40 GHz. After the analysis of the measurements, the clustering of the PDP (Power Delay Profile) has been carried out, grouping different multipath contributions with similar delays and amplitudes. Finally, using the outcome from clustering, the PDP has been parameterized using the Saleh­-Valenzuela model as a reference.

[ES] En este TFM se implementará una sonda de medida para la caracterización del canal radio en la banda de milimétricas. La sonda estará basada en un enlace de radio sobre fibra para evitar las elevadas pérdidas de propagación que introducen los cables a estas frecuencias. La sonda incorporará un sistema de posicionamiento en transmisión y recepción para permitir una caracterización MIMO del canal. La sonda se implementará en el dominio del tiempo haciendo uso de un analizador de redes vectorial.

[ES] Este Trabajo Fin de Máster (TFM) presenta el análisis experimental de un canal MIMO masivo en un entorno de oficina en ondas milimétricas. La técnica de MIMO masivo está considerada una tecnología habilitadora para conseguir grandes capacidades de red en escenarios multiusuario. En este trabajo, se investiga el rendimiento de un sistema MIMO masivo a partir de datos medidos un escenario de interiores, en concreto, en una oficina desde 25 hasta 40 GHz en el dominio de la frecuencia, usando un array virtual rectangular de 144 (12×12) antenas en la estación base. Se ha considerado tanto la condición de propagación de vista directa como de vista con obstrucción de la componente directa. A partir de esta campaña se investiga la condición favorable de propagación y la capacidad alcanzable en función del número de usuarios activos y el número de antenas ubicadas en la estación base. Los resultados se han particularizado en las bandas de 26, 28 y 38 GHz por ser las bandas de frecuencia adoptadas para las futuras generaciones de comunicaciones móviles (5G en adelante)., [EN] This Final Master¿s Project presents the experimental analysis of a massive MIMO channel at milimeter waves in an office environment. Massive MIMO is considered an enabling technology to achieve large network capacities in multi-user scenarios. In this project, the performance of the mas- sive MIMO concept is investigated from measurement data at millimeter wave (mmWave) frequency bands. The measurements were collected in an indoor office environment from 25 to 40 GHz in the frequency domain, using a virtual uniform rectangular array (URA) at the base station consisting of 144 (12×12) antennas. Line-of-Sight (LOS) and Obstructed-LOS (OLOS) propagation conditions have been considered. Both the favorable propagation condition and the achievable capacity are analysed in terms of active users and number of antennas placed at the base station. The results are particularised at the 26, 28 and 38 GHz bands adopted for the deployment of future wireless communication networks (5G and beyond).

[ES] En el TFM se analizarán las características de dispersión del canal radio como consecuencia del efecto multicamino, proponiendo una metodología para el análisis del scattering difuso que permita su modelado en simuladores de canal basados en el concepto de trazado de rayos, [EN] In this TFM proposal, the main features of the propagation channel dispersion due to the mutipath effect at millimeter wave frequencies will be analyzed from channel measurement data. A metodology to model the diffuse scattering will be proposed from specular and dense multipath compoments. The diffuse scattering model will improve the accurary of channel models and simulators based on the ray-tracing concept.

[EN] Recent standardization of portions of the millimeter-wave (mm-wave) band for fifth-generation (5G) operation has called for further research on how short-term fading behaves in that unexplored part of the spectrum. With such a target, this paper reports on a thorough measurement campaign conducted in an indoor environment characterized by rich-multipath scattering, a part of a modern building, with floor and ceiling constructed of reinforced concrete over steel plates with wood and plasterboard-paneled walls. Particularly, measurements have been performed in a variety of scenarios, under line-of-sight (LoS) and non-line-ofsight (nLoS) conditions, for a wide range of frequencies, namely from 25 to 40 GHz - a span of 15 GHz - therefore, including 26, 28 and 39 GHz. First and second order statistics of representative fading models, namely Rayleigh, Rice, Nakagami, folded normal, alpha-mu, eta-mu, kappa-mu and alpha-eta-kappa-mu have been investigated. The metrics used in the analysis were the normalized mean square error (NMSE), the Kolmogorov-Smirnov (KS), and the Akaike information criterion (AIC). Additionally, the study of the kappa-mu. model is advanced, in which new, exact, simple closed-form expressions for probability density function, cumulative distribution function, and level crossing rate are derived for some particular cases, namely for mu = n + 1/2 in which n is an element of N.

[ES] El objetivo de este trabajo es proponer modelos experimentales de las pérdidas de propagación para canales de comunicación en entornos indoor. Se ha efectuado una caracterización experimental de las pérdidas de propagación de acuerdo con la campaña de medidas llevada a cabo en un escenario típico de un campus universitario. Estas medidas fueron realizadas en un ambiente de laboratorio a 3.7 GHz en condiciones de línea de vista y con un enfoque de banda estrecha. Las mediciones se hicieron en la noche, simulando condiciones de estacionariedad del canal de comunicaciones. Los resultados obtenidos muestran los valores de los parámetros del modelo Close-In (CI) a una distancia de referencia en espacio libre, y del modelo FloatingIntercept (FI) en términos de la distancia de separación entre el transmisor y receptor. Se debe notar que dichos valores de los modelos de pérdidas de propagación se han extraído aplicando técnicas de regresión lineal a los datos medidos. Además, concuerdan con los valores del exponente de pérdidas de propagación presentados por otros investigadores en escenarios similares. Con la implementación de estos modelos se puede describir el comportamiento de las pérdidas de propagación en este tipo de entornos, sin embargo, es necesario hacer más campañas de medición para mejorar los conocimientos de las características del canal de propagación. También, para obtener una mejor precisión en los resultados obtenidos, con el fin de optimizar el despliegue y desempeño de las futuras redes de quinta generación (5G), que combinen los entornos indoor para la prestación de sus servicios y aplicaciones., [EN] The objective of this work is to propose experimental path loss propagation models for communication channels in indoor environments. In this sense, an experimental path loss characterization has been achieved, according to the measurements campaign carried out in a typical scenario of a university campus. These narrowband measurements were collected in the laboratory environment at 3.7 GHz in line-of-sight (LOS) condition. Also, these measurements were carried out at night to simulate stationary channel conditions. Thus, the results obtained show the values of the parameters of the close-in (CI) free space reference distance and floating-intercept (FI) path loss models, in terms of the transmitter and receiver separation distance. It should be noted that these values of the path loss models have been extracted applying linear regression techniques to the measured data. Also, these values agree with the path loss exponent values presented by other researchers in similar scenarios. The path loss behavior can be described with the implementation of these models. However, more measurement campaigns are needed to improve the understanding of propagation channel features, as well as to obtain better precision in the results obtained. This, in order to optimize the deployment and performance of next fifth-generation (5G) networks that combine indoor environments to offer their services and applications.

[ES] En el TFM se abordará el modelado de las pérdida de propagación en un escenario de oficina a 10 GHz a partir de los modelos propuestos en el proyecto europeo WINNER-II y adoptados por el 3GPP. Para ello se hará uno de los resultados de medidas de propagación disponibles en la banda de 10 GHz. Se analizará también el efecto de dispersión temporal y selectividad espacial y en frecuencia mediante el parámetro K de la distribución Rice.

[ES] En los futuros sistemas 5G en banda de milimétricas se utilizarán anchos de banda de varios centenares de megahercios. El objetivo del TFG es analizar experimentalmente los efectos de selectividad en espacio y frecuencia a partir de medidas obtenidas en el dominio de la frecuencia en un escenario de oficina., [EN] Bandwidths of several megahertz will be used in the future 5G networks at millimeter wave frequencies. The objective of the TFG is to analyze the space and frequency selectivity from channel measurements performed in the frequency domain in an office environments.

[ES] En el presente Trabajo Final de Grado se analiza el efecto de interferencia que genera la señal de telefonía móvil en la banda de 800 MHz sobre la señal de Televisión Digital Terrestre. Para ello, se evalúa la consecuencia que puede tener la coexistencia de ambas señales en la misma zona geográfica, analizando el efecto de interferencia que genera la señal interferente para los enlaces de Uplink y Downlink. Para la comprensión teórica del análisis llevado a cabo, se hace un estudio de los estándares de ambas señales y se profundiza en los fundamentos teóricos de la señal interferida, que hace adquirir los conceptos necesarios para la comprensión de la problemática. Previo al análisis, se estudian los posibles escenarios que se pueden encontrar según la canalización de la región, dentro de estos posibles escenarios se analiza el peor caso en cuanto a interferencia se refiere. Además, a modo comparativo y sirviendo de guía, se refleja el estudio de interferencia realizado por un organismo Europeo y la experiencia llevada a cabo en la gestión del proyecto en el Reino Unido. Para el análisis, se emplea dispositivos electrónicos para generar las señales de ambas tecnologías. Haciendo uso de un medidor de campo, del ámbito laboral, se estudian los márgenes de protección necesarios entre ambas señales, así como la mejora que produce cuando hacemos uso de filtros aplicando el protocolo de actuaciones que rige el Ministerio de Industria Energía y Turismos en la orden IET/32972015 tras la obligación interpuesta por el Real Decreto 458/2011. Tras la comprensión del análisis efectuado y aprovechando la oportunidad que se me presentó en el ámbito laboral, se expone de una manera práctica un caso real de afectación entre ambas señales, consiguiendo solventar el problema de interferencia mediante la aplicación del protocolo de actuación para situaciones especiales., [EN] In this Final Degree Project it¿s analyzed the effect of interference generated by mobile phone signal in the band of 800 MHz on the digital terrestrial television signal. For this purpose, the consequence of having both signals coexisting in the same geographical area is evaluated, analyzing the effect of interference generated by the interference signal for Uplink and Downlink links. To the theoretical understanding of conducted analysis, a study about the standards of the two signals is made and delves into the theoretical foundations of the interfered signal, which makes acquiring the necessary concepts for the understanding of the problem. Prior to analysis, the possible scenarios that can be found according to the region in question are studied, specifically the worst situation regarding interference within the possible cases. Moreover, comparatively and serving as a guide, it is taken into consideration the study of interference carried out by an European agency as well as the management experience from the project carried out in the UK. For the analysis, electronic devices are used to generate the signals of both technologies. Using a field strength meter from the labor sphere, protection margins needed between the two signals are studied as well as the improvement that occurs when we use filters applying the action protocol which is governed by the Ministry of Industry, Energy and Passenger cars in the IET / 32972015 order, after the obligation from the Royal Decree 458/2011. After the comprehension of the analysis carried out, and taking advantage of the opportunity that was presented to me in the labor sphere, a real case of affectation between the two signals is exposed in a practical way, thus getting solve the interference problem by the application of the protocol for special situation.

[ES] En un canal radio el efecto multicamino provoca dispersión temporal, lo que se traduce en un aumento de la probabilidad de error de bit en sistemas de comunicaciones móviles digitales. Una correcta caracterización del canal es la base para el diseño óptimo de todo sistema de transmisión por radio. El objetivo del TFG es diseñar y automatizar una sonda de canal en el dominio de la frecuencia que permita medir experimentalmente el efecto de dispersión temporal, o selectividad en frecuencia, introducido por el canal radio., [EN] In a radio channel, the multipath effect causes temporal dispersion, increasing the bit error rate in digital wireless communication systems. A proper characterization of the channel is the basis for the optimal design of any radio transmission system. The objective of this TFG is to design and automate a channel sounder in the frequency domain that allows us and experimental characterization of the temporal dispersion, or frequency selectivity, introduced by the radio channel.

[ES] El objetivo del TFG es analizar la dispersión temporal y angular del canal radio en un escenario típico de oficina. Partiendo de medidas experimentales realizadas en el domino de la frecuencia, se evaluarán los principales parámetros que permiten caracterizar la dispersión temporal y angular. Se implementarán algoritmos de detección de contribuciones multicamino, cuyos resultados permitirán evaluar el comportamiento dispersivo, relacioándolo con la distancia entre transmisor y receptor., [EN] In this TFG, the temporal and angular dispersion of the radio channel in a typical office environment will be analyze. From experimental measurements carried out in the frequency domain, the main parameters that characterize the temporal and angular dispersion of the propagation channel will be evaluated. Multipath contribution detection algorithms will be implemented in order to find the number of multipath contributions and their delay, amplitud and direction of arrival. The relationschip among the dispersion metrics and transmitter-receiver distance will be also investigated.

[EN] This paper presents an analysis of the massive MIMO channel in an indoor picocell. The analysis is based on the results of a measurement campaign carried out in the 3.2 to 4 GHz band in a scenario of reduced size and with a symmetrical geometry. It is well known that the performance of massive MIMO systems depends largely on the fact that the radio channel meets the condition of favorable propagation. In order to evaluate the performance of the resulting massive MIMO channel, results concerning the sum capacity are included. A second factor that determines the performance of massive MIMO systems when it is operated in a TDD-OFDM framework is the frequency selectivity of the channel that limits the size of the coherence block. In this sense, results of the coherence bandwidths achieved are also presented and analyzed.

[EN] In this conference contribution, we present millimeter-wave (mmWave) propagation measurements for an office environment from 25 to 40 GHz and investigate the path loss using the most common empirical models proposed in WINNER-II and adopted by the 3GPP: the single-frequency floating-intercept (FI) model, the single-frequency close-in (CI) free space reference distance model, the multi-frequency alphabeta-gamma (ABG) model and the close-in free space reference distance with frequency path loss exponent (CIF). Both line-ofsight (LOS) and obstructed-LOS (OLOS) propagation conditions have been considered. The mean value of the model parameters, and their 95 % confidence intervals, have been derived using regression and optimization techniques.

[EN] In this work, an analysis of the Rician K-factor in a laboratory environment from 25 to 40 GHz has been carried out. The variation of the estimated K-factor has been assessed in frequency from a channel measurements campaign in both line-of-sight (LOS) and non-LOS (NLOS) conditions. Mean values of the K-factor ranging from 0.48 to 3.43 dB for LOS conditions, and from -5.54 to -0.56 dB for NLOS conditions, have been derived. The results reported here enable us to get insight into the propagation channel characteristics and can be of interest to evaluate the performance of fifth-generation (5G) networks in laboratory environments.

[EN] In this contribution, we present a method for estimating the optimal size of moving average filter to ensure a precise separation of small and large scale fading effects. The analysis of small and large scale fading of the Vehicle-to-Vehicle (V2V) measured channel has been performed from narrowband channel measurements carried out in an urban environment at 5.9 GHz. Uniform intervals, where the channel process can be considered stationary, have been identified by comparing the cumulative distribution function (CDF) of the received envelope. A relationship between the length of the uniform intervals and the velocity of vehicles has been found. Moreover, the Rice K factor has been estimated for each one of these intervals. Our results showed that the proposed method is adequate to carry out a small and large scale fading separation. The results obtained make its use interesting to process correctly measured data in vehicular environments.

[ES] El objetivo de este trabajo fin de máster es utilizar un sistema Massive MIMO para cargar nodos BLE inalámbricamente. En primer lugar, se ha estudiado la necesidad de un diseño hardware específico y se ha producido. En segundo lugar, se ha estudiado la relación entre la tasa de transmisión del nodo BLE y los parámetros de transferencia de energía inalámbrica. Finalmente, se ha establecido el rendimiento del sistema completo., [EN] The goal of this thesis is to use the Massive MIMO channel beacon concept to power BLE nodes, wirelessly. Firstly, the necessary receiver hardware is designed and produced. Next, the relation between BLE datarate and wireless power transfer parameters is studied. Finally, using experiments, the performance of the wireless powered BLE system is verififed.

[ES] En este Trabajo de Fin de Grado (TFG) se ha llevado a cabo la caracterización angular del canal en la banda mmWave (de 25 GHz a 40 GHz) a partir del algoritmo MUltiple SIgnal Classi cation (MUSIC), mediante la de finición de un Array Rectangular Uniforme (URA). Inicialmente, se realizó el estudio del estado del arte y comprensión de dicho algoritmo y de otros trabajos similares donde se aborda el tema de la caracterización angular. Las medidas realizadas contemplan las condiciones de visión directa (LOS) y no visión directa (NLOS). El análisis de las medidas se ha realizado a través de una serie de scripts en MATLAB. Así, se han obtenido resultados respecto al tamaño del URA en función de la dispersión angular, la anchura que presentan las contribuciones principales en función del tamaño del URA, el número de contribuciones que llegan a la antena a partir de su potencia, retardo y ángulo, la correlación que presentan en conjunto todas las medidas y la relación de la dispersión angular frente a la distancia., [EN] In this Final Degree Project (TFG) it has been carried out the angular characterization channel in the mmWave band (25 GHz to 40 GHz) using the MUltiple SIgnal Classi cation (MUSIC) algorithm, with the de finition of an Uniform Rectangular Array (URA). Initially, it has made the compression and study of the state of art for this algorithm and other similar works that address the angular characterization issue . The measurements taken into the account the Line-Of-Sight (LOS) and Non Line-Of-Sight (NLOS). The measurements analysis had been made through some scripts on MATLAB. Thus, it has been got the results for the size of the URA anntena according to angular spread, the principal contributions width based on the size of the URA anntena, the number of the contributions that arrived at the anntena from the power, the delay and the angle, the correlation of the all measurements and the relationship between the angular spread and the distance.

[EN] In this paper, path loss and time-dispersion results of the propagation channel in a typical office environment are reported. The results were derived from a channel measurement campaign carried out at 26 GHz in line-of-sight (LOS) and obstructed-LOS (OLOS) conditions. The parameters of both the floating-intercept (FI) and close-in (CI) free space reference distance path loss models were derived using the minimum-mean-squared-error (MMSE). The time-dispersion characteristics of the propagation channel were analyzed through the root-mean-squared (rms) delay-spread and the coherence bandwidth. The results reported here provide better knowledge of the propagation channel features and can be also used to design and evaluate the performance of the next fifth-generation (5G) networks in indoor office environments at the potential 26 GHz frequency band.

(c) 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, 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 components of this work in other works., [EN] A thorough measurement campaign in an indoor environment at the millimeter-wave band is carried out with an aim at characterizing the short-term fading channel in terms of its higher-order statistics. The measurements are conducted in a variety of scenarios, with frequencies ranging from 55 to 65 GHz, in line-of-sight and non-line-of-sight conditions, and combinations of horizontal and vertical polarizations at both the transmitter and the receiver. A number of fading models are tested, namely Rayleigh, Rice, Nakagami-m, alpha-mu, kappa-mu, eta-mu, and alpha-eta-kappa-mu. The main second-order statistics under analysis are the level crossing rate (LCR) and average fade duration (AFD) both given per distance unit. From the experimental data, the parameters of these statistics are estimated, and the corresponding curves of the theoretical models are compared with the empirical ones and the best model is selected. Additionally, the study of the very general distribution, namely alpha-eta-kappa-mu, is advanced, in which new expressions for time-/distance-domain LCR and Al-ll are derived using an envelope-based approach. Such an approach leads to integral-form formulations with much less computational complexity and computes rapidly compared with the already existing ones presented elsewhere, also given in the integral form. Furthermore, a series of expansion expression for the alpha-eta-kappa-mu time-/distance-domain LCR is then derived that improves even further the computational time.

(c) 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, 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 components of this work in other works., [EN] Concerning the design and planning of new radio interfaces for the fifth-generation (5G) systems, this paper presents a useful contribution to the characterization of the wideband indoor radio channel in the 3-4-GHz frequency band. A measurement campaign has been carried out in two different indoor scenarios to analyze some of the most important wideband parameters of the propagation channel, including a thorough analysis of its behavior to meet the new radio technology challenges. The channel measurement setup consists of a virtual vertical uniform array at the receiver side of the link that remains at a fixed position, whereas the transmitter side, which is equipped with a single antenna, is placed at different positions in the environment under analysis. The measurement setup emulates the up-link of a multi-user multiple-input multiple-output (MIMO) system and allows obtaining the broadband parameters of the multiple channels that are established between the transmitter and each one of the antennas of the receiver array. The results and conclusions about the path loss, temporal dispersion, and coherence bandwidth are included, along with an analysis of the spatial correlation between wideband channels when one of the antennas is an array.

© 2019 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng 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., [EN] In this letter, the dependence of the specular multipath components (SMC) and dense multipath components (DMC) to the interuser spatial correlation and sum-rate capacity of a massive multiuser multiple-input--multiple-output (MU-MIMO) setup is evaluated from measurements conducted inside an underground subway wagon at the 25-40 GHz candidate frequency bands for 5G systems. The radio channel consists in a 7 7 uniform rectangular array (URA) acting as access point for eight users uniformly distributed in the wagon. The DMC power ratio is observed to be distance- and frequency-dependent as the SMC and DMC exhibit different propagation mechanisms. Remarkably, it is reported that the interuser spatial correlation computed with DMC offers the best favorable propagation for a massive MIMO setup, whereas SMC contribute to the users correlation. Hence, correlation is found to be strongly dependent on the DMC ratio frequency characteristics. In addition, better interuser correlation and sum-rate capacity values are obtained as the frequency is increased. These results highlight the need to include DMC in 5G massive MIMO channel models and emulators to improve their accuracy at the system level.

[EN] A thorough millimeter-wave measurement campaign is carried out in an indoor environment with an aim at characterizing the short-term fading channel behavior. The measurements are conducted in a variety of scenarios, with frequencies ranging from 55 GHz to 65 GHz, in line-of-sight and non-line-of-sight conditions, and combinations of horizontal and vertical polarizations at both transmitter and receiver. A number of fading models are tested, namely Rayleigh, Rice, Nakagami-m, alpha-mu, kappa-mu, eta-mu, and alpha-eta-kappa-mu. The statistics under analysis are those characterizing the fading amplitude and the frequency selectivity. In particular, the probability density and cumulative distribution functions for the former and level crossing rate per bandwidth unit for the latter are the respective first-and second-order statistics used. To this end, from the experimental data, the parameters of the models are estimated and the corresponding theoretical curves are plotted and compared with the empirical ones. Whereas the required theoretical formulations of the first-order statistics of these models are already well known, those of the second-order statistics as well as these fitting process in such a band shown here are unprecedented in the literature.

[EN] This study presents an analysis of the capabilities of using multi-user multiple input multiple output (MU-MIMO) in indoor environments at the 3-4 GHz band through an empirical characterisation of the MU-MIMO channel, obtaining a statistical description of the degree to which this specific multi-user channel verifies the condition of 'favourable propagation'. Different metrics have been considered to measure the degree of orthogonality between the channels, such as the orthogonality coefficient or the condition number. In addition, in order to obtain a direct measure of the goodness of the channel in terms of the achievable spectral efficiency, the capacity of the channel has been calculated for different numbers of users and base station antennas and compared with theoretical i.i.d. Rayleigh channels.

© 2019 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng 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.", [EN] In this correspondence, useful measurement results of the propagation channel characteristics in an intra-wagon environment at millimeter wave (mmWave) frequencies are presented. The measurements were collected inside an underground convoy from 25 to 40 GHz in the frequency domain. A broadband radio over fiber (RoF) link was used in order to avoid the high losses introduced by cables at these frequencies, thus allowing long distances between the transmitter and receiver antennas. Values of the path loss exponent and delay spread are reported at the potential 26, 28 and 38 GHz bands to deploy the future fifth-generation (5G) systems. These results allow us to have a better knowledge of the path loss and time dispersion characteristics of the propagation channel in this particular environment, characterized by rich-scattering with long delays.

(c) 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, 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 components of this work in other works., [EN] In this paper, a novel form of the folded normal (FN) distribution has been proposed to model the small-scale fading in wireless communications. From a multiple-input multiple-output (MIMO) measurement campaign conducted in a lab environment with the line-of-sight (LOS) conditions at both the 60 and the 94 GHz bands, the authors obtain the parameters of the Rician, FN, and kappa-mu distributions. These parameters have been calculated by using the least square (LS) approximation and with techniques of statistical inference. The FN distribution provides the best fitting to the experimental results using the Kolmogorov-Smirnov (K-S) test for the inferred estimators with values of the ful llment of 100% and 69.82% at the 60 and 94 GHz bands, respectively, for a significance level of 1%.

[EN] In this paper, estimators of the Nakagami-lognormal (NL) distribution based on the method of log-moments have been derived and thoroughly analyzed. Unlike maximum likelihood (ML) estimators, the log-moment estimators of the NL distribution are obtained using straightforward equations with a unique solution. Also, their performance has been evaluated using the sample mean, confidence regions and normalized mean square error (NMSE). The NL distribution has been extensively used to model composite small-scale fading and shadowing in wireless communication channels. This distribution is of interest in scenarios where the small-scale fading and the shadowing processes cannot be easily separated such as the vehicular environment.

[ES] El TFG consiste en describir el proceso de implantación y posterior certificación de una tecnología, en este caso LTE en banda 1800, en un emplazamiento realizando para ello un replanteo del emplazamiento y aportando las soluciones técnicas necesarias para llevar a cabo dicha reforma, tales como, elección de nuevas BBU's, nuevas RRU's, nuevas antenas en caso de que sean necesarias, realizar el estudio de emisiones radioeléctricas, calculo de los volúmenes de referencia, etc...de acuerdo con la normativa vigente y con las reglas de diseño establecidas con el fin de conseguir la mejor solución en términos de eficiencia y coste. Se describirán los pasos y tramites legales que se han de llevar a cabo para poder certificar la reforma.

[ES] Haciendo uso de la herramienta LinkPlanner y de los equipos proporcionados por Cambium Networks se implementará el acceso a Internet en la zona de Millares y Dos Aguas de forma inalámbrica. Se diseñarán los enlaces radio necesarios y se analizará la cobertura en términos de potencia y disponibilidad.

[ES] El objetivo del TFG es realizar una caracterización del canal radio en la banda de milimétricas a partir del empleo de técnicas de trazado de rayos. Se hará uso de la herramienta CINDOOR, cuyos resultados se contrastarán con los obtenidos a partir del análisis de una campaña de medidas realizada en las instalaciones de iTEAM en la banda de 25 a 40 GHz., [EN] The objective of this Final Degree Project is carrying out the radio channel characterisation on the mmwave band by using ray tracing techniques. Tool CINDOOR will be used, whose results will be compared to the ones obtained from the analysis of a measurements campaign made in the iTEAM's installations on the frequency band from 25 to 40 GHz.

[ES] Las radiaciones y partículas ionizantes presentes en entornos espaciales son potencialmente dañinas para los dispositivos EEE (Electrónicos, eléctricos y electromecánicos) embarcados en los satélites. Por ello, es necesario realizar un estudio previo para asegurarse de la supervivencia de estos dispositivos durante la misión. Se propone desarrollar un software que permita obtener, de forma sencilla para el usuario, datos sobre las dosis de radiación absorbida por componentes electrónicos en misiones de vuelo en entorno espacio basándose para ello en librerías públicas (Geant4 y SPENVIS). El usuario podrá definir la geometría tridimensional del modelo y, a continuación, realizar un análisis que permita obtener el espesor de blindaje y la dosis de radiación absorbida para cada componente presente en el modelo.

[ES] A partir de los resultados de una campaña de medidas en la banda de 25 a 40 GHz realizada en las instalaciones de iTEAM, en lo que puede considerarse un entorno de oficina, se analizará la capacidad de un sistema MIMO multiusuario. Las medidas de las que se dispone permiten implementar analizar un sistema MIMO de dimensiones 144x14, tanto en situación de visión directa como con obstrucción de la componente principal. Los resultados que se obtengan puede ser de interés en el despliegue de las futuras redes 5G en la banda analizada.