Leandro Juan‐Llácer

Universidad Politécnica de Cartagena

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José‐María Molina‐García‐Pardo

Universidad Politécnica de Cartagena

134

José‐Víctor Rodríguez

Universidad Politécnica de Cartagena

104

Juan Pascual‐García

Sociedad Española de Medicina Interna

Concepcion Garcia‐Pardo

Universitat Politècnica de València

María‐Teresa Martínez‐Inglés

Ministerio de Defensa

M. Liénard

Université de Lille

Ignacio Rodríguez‐Rodríguez

Universidad de Málaga

Lorenzo Rubio

Universitat Politècnica de València

Concepción Sanchis-Borrás

Universidad Católica San Antonio de Murcia

Narcís Cardona

Universitat Politècnica de València

Cooperative Institutions

Universidad Politécnica de Cartagena

Division of Undergraduate Education

Universitat Politècnica de València

University of Cartagena

Institut d'électronique de microélectronique et de nanotechnologie

Université de Lille

Centre National de la Recherche Scientifique

Universitat de València

Universitat Politècnica de Catalunya

Universidad de Alcalá

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RADIOGIS software que puede incorporarse como una nueva barra de herramientas a Arcview 9 para el cálculo de cobertura radioeléctrica de sistemas de radiocomunicación.

Leandro Juan‐Llácer

[ESP]1. Calculos: • Coberturas de potencia, de campo electrico o de densidad de potencia. Modelos de propagacion: Entorno rural: Meeks y UITR-526- Entorno urbano: Hata, COST231 y Xia-Bertoni.- Indoor: Trazado de rayos y UTD.• Porcentaje sobre umbral: utilizando una capa vectorial que contenga terminos municipales, terminos provinciales, carreteras, comarcas, distritos municipales, etc.; o bien sobre un poligono, linea o rectangulo.2. Gestion de Bases de Datos. • De emplazamientos.• De coberturas radioelectricas de potencia.• De mapas de densidad de potencia o de campo electrico.• De sistemas de potencia. • De mapas multiples de potencia o de campo electrico.• Campanas de medidas.• Operaciones de gran utilidad con informacion raster.[ENG] 1. Calculations • Power, electric field or power density coverage • Propagation models: - Rural environment: Meeks and UITR-526 - Urban environment: Hata, COST231 and Xia-Bertoni - Indoor: Ray tracing and UTD • Percentage over threshold using a vectorial layer which includes municipal areas, provincial areas, roads, districts, etc. or with reference to a polygon, a line or a rectangleB. Management of Databases• Location databases • Power radioelectric coverage databases • Power density or electric field maps databases• Power systems databases • Multiple power or electric field maps databases • Measurement campaigns • Highly useful operations with raster information databases

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Problemas resueltos de sistemas de telecomunicación (Vol. I)

Leandro Juan‐Llácer José‐María Molina‐García‐Pardo Juan Pascual‐García José‐Víctor Rodríguez

Los problemas que se presentan en este libro están relacionados con los sistemas y servicios de telecomunicación que se estudian en las Escuelas de Ingeniería de Telecomunicación. Todos los problemas se explican detalladamente, utilizando las fórmulas y figuras necesarias para ayudar a la compresión de cada uno de ellos. Esta colección de problemas se ha estructurado en las siguientes partes: Niveles, Tráfico, Ruido, Medios de transmisión en línea, Comunicaciones móviles y Radioenlaces. Esta lista se completa con un capítulo denominado Problemas Generales en el que se incorporan aquellos problemas más complejos que incluyen varias temáticas incluidas en los capítulos anteriores. En las dos primeras partes del libro se tratan materias básicas en el estudio de cualquier sistema de telecomunicaciones. Así, en la primera parte se hallan los problemas relacionados con la utilización de unidades y magnitudes en escala logarítmica. El manejo de estas unidades y magnitudes es fundamental para el diseño y comprensión de cualquier sistema de telecomunicaciones. En la segunda parte del libro se presentan los problemas relacionados con el estudio del tráfico de telecomunicaciones. Este estudio nos permitirá dimensionar de forma adecuada los servicios que se proporcionan en los sistemas de telecomunicación. Así, se aprende a calcular el número de canales necesario para satisfacer una cierta demanda de tráfico con una calidad predeterminada. Las dos siguientes partes del libro se refieren a aspectos más concretos de los sistemas de telecomunicaciones: en la tercera parte se hallan los problemas relacionados con el estudio y análisis del ruido en sistemas de telecomunicaciones y en la cuarta parte se encuentran problemas donde se calculan los parámetros primarios de un cable. Dichos parámetros son la resistencia, inductancia o capacitancia por unidad de longitud de un cable a partir de su geometría y de las características de los materiales que se han empleado en su fabricación (permitividad, conductividad, etc.), y se relacionan con los parámetros secundarios (impedancia característica, atenuación,…) que son los que se suelen utilizar a la hora de planificar, por ejemplo, la instalación de un sistema de televisión por cable. En la quinta y sexta partes del libro se estudian dos sistemas reales de telecomunicaciones. La quinta parte se centra en la planificación de sistemas de comunicaciones móviles, y se revisan, por tanto, conceptos como el de la cobertura radioeléctrica y la planificación celular. En la sexta parte, se presentan problemas relacionados con las radiocomunicaciones punto a punto. Estos enlaces permiten en la actualidad la transmisión de gran volumen de datos entre dos puntos vía radio. Finalmente, en la séptima parte se encuentran los problemas cuya temática es general y no se ha podido asignar en los capítulos anteriores de forma única.

10.31428/10317/8460

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CARACTERIZACION MIMO DE UNA ESQUINA MEDIANTE MEDIDAS

Rubén Ibernón Fernández José‐María Molina‐García‐Pardo Leandro Juan‐Llácer

This paper presents results on capacity, correlation and K-factor for a 4x4 MIMO system in a microcellular environment. A MIMO channel sounder based on a multiport network analyzer and a fast switch controlled by a laptop has been used. LoS and NLoS situations are distinguished for three antenna elements separation of the arrays each. It has been appreciated a low capacity in some positions of the NLoS situation in spite of a not very high correlation.

Non-line-of-sight propagation

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MEDIDAS DEL CANAL MIMO EN LA TRANSICION DE ENTRADA A UN PEQUEÑO TUNEL

José‐María Molina‐García‐Pardo Leandro Juan‐Llácer José‐Víctor Rodríguez

Los autores agradecen al Ministerio de Educacion y Ciencia (TEC2004-04866-C04-04/TCM) y a la Fundacion Seneca (PPC/01444/03) por financiar este trabajo.

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Doppler Characterization in Ultra Wideband BAN Channels During Breathing

IEEE Transactions on Antennas and Propagation (2019)

Ruben-Gregorio Garcia-Serna Concepcion Garcia‐Pardo José‐María Molina‐García‐Pardo Leandro Juan‐Llácer Narcís Cardona

Monitoring the physical parameters from devices inside the body, using ultra wideband (UWB) technology, enables the development of high bandwidth demanding applications in real time. The relative movement of the nodes deployed in the body, due to breathing, can give rise to a frequency shifting effect, increasing the fading level in the propagation channel during transmissions. In this article, therefore, we present a study of the frequency effects on the propagation channel derived from the relative movement between two nodes of a wireless body area network (WBAN), at least one of them placed inside the human body, caused by breathing. The study is performed on the basis of the Doppler spectrum characterization in terms of the shape fitting and frequency spread parameter derivation. Continuous wave (CW) signals have been used to cover the UWB range at four selected frequencies: 3.1, 4.8, 6, and 8.5 GHz, and a liquid phantom has been employed for emulating the dielectric properties of the high water content tissues at the considered UWB frequencies.

Wideband

Body area network

Radio spectrum

Extremely high frequency

10.1109/tap.2019.2951849

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Evaluation od MIMO capacity in regular and chaflane street cornersfor microcellular communications

José‐María Molina‐García‐Pardo José‐Víctor Rodríguez Leandro Juan‐Llácer

In this paper, a ray launching model based on the application of the uniform theory of diffraction (UTD) and geometrical optics (GO) has been implemented for modelling the propagation in MIMO microcellular urban scenarios. This model has been used to analyse the behaviour of the capacity in two street corners environments: Regular and chaflane street corners. The study of the environment of the two corners shows that there exist important differences between both street scenarios: capacity is higher in chaflane street corners. Finally the impact of the orientation of the transmitter and receiver is studied in terms of capacity.

10.1109/pimrc.2003.1260365

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MIMO capacity in a pedestrian passageway tunnel excited by an outside antenna

HAL (Le Centre pour la Communication Scientifique Directe) (2011)

José‐María Molina‐García‐Pardo M. Liénard P. Degauque Leandro Juan‐Llácer

Numerous papers have already been published on the improvement of the channel capacity which can be obtained by using Multiple Input Multiple Output techniques. Various environments have been studied as indoor and urban environment. Since there is also a need to cover tunnels, recent works deal with the characterization of the channel transfer matrix in order to predict the performance of the link in such a configuration. However it was always assumed that both the transmitting antenna and the receiving antenna are situated inside the tunnel. Since, for short tunnels, an additional fixed antenna inside the tunnel is not always necessary, the objective of this paper is to examine the case of a mobile entering and moving inside a tunnel excited by an outside antenna. Since the capacity depends both on the path loss and on the correlation between array elements, a parametric study shows the influence of the offset angle characterizing the direction of the fixed antenna array referred to the tunnel axis. Results are based on experiments carried out in a pedestrian tunnel and at a frequency of 2.45 GHz.

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Frequency selective wallpaper for reducing interference while increasing the MIMO capacity in indoor environments

José‐Víctor Rodríguez Mats Gustafsson Fredrik Tufvesson Anders Karlsson Leandro Juan‐Llácer

The design and features of frequency-selective wallpaper created for attachment onto regular walls in order to filter out signals operating at 5 GHz while at the same time allowing the desired radio communication services to propagate through such walls are presented. An analysis of the characteristics of the radio channel evaluated in a typical indoor environment, when considering either regular walls or walls with the designed wallpaper, is performed through a ray-launching programme for both single input single output (SISO) and multiple input multiple output (MIMO) systems. In this way, parameters such as the signal to interference ratio, power delay profile, and channel capacity are obtained and compared for the two mentioned scenarios (with and without wallpapers). (6 pages)

Wallpaper

SIGNAL (programming language)

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An attenuation function expressed in terms of UTD coefficients for the multiple-wedge diffraction considering spherical-wave incidence

2021 IEEE 94th Vehicular Technology Conference (VTC2021-Fall) (2005)

José‐Víctor Rodríguez José‐María Molina‐García‐Pardo Leandro Juan‐Llácer

An attenuation function expressed in terms of UTD coefficients for the prediction of the multiple diffraction produced by an array of perfectly conducting wedges considering spherical-wave incidence is presented. The solution, validated with numerical results from the technical literature, sharply reduces the computing time over an existing formulation when the number of wedges is large. The result could be applied in the planning of microcellular mobile radio systems.

Wedge (geometry)

Spherical wave

10.1109/vetecf.2004.1399977

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The use of semi-deterministic propagation models for the prediction of the short-term fading statistics in mobile channels

Lorenzo Rubio Narcís Cardona S.J. Flores Juan Reig Leandro Juan‐Llácer

In this paper, a semi-deterministic propagation model for the prediction of short-term fading statistics in urban mobile cellular systems is presented. The model is based on digital map information and is also used to predict coverage areas. The short-term fading is modelled by the Nakagami distribution, where the two parameters defining the distribution for a local area around the mobile position can be obtained from the available digital map information of the urban area. Computer simulation results and measurement campaigns are compared, showing that the best approximation to the probability density function of the short-term fading in mobile urban channels is a Nakagami distribution.

Nakagami distribution

Fading distribution

Position (finance)

10.1109/vetecf.1999.801504

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