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Ítem DVB Coverage Prediction Using Game Engine Based Ray-Tracing Techniques(IEEE, 2011-09-05) Gimenez, Jordi J.This paper presents the results of an evaluation of a propagation model based on ray-tracing techniques using a game engine and Graphics Processing Unit (GPU) in outdoor scenarios, as a gap-filler for a Digital Video Broadcasting Handheld (DVB-H) service. This model involves complete identification of the parameters of wave propagation, multipath components between the transmitter and the receiver as attenuation, time delay of arrival (TDA), full polarimetric transmission matrix, direction of arrival DoA and the direction of departure DoD. In the paper, we present the results of the simulation and compare them with measurements, obtaining a satisfactory fit. © 2011 IEEE.
Ítem Applicability of Game Engine for Ray Tracing Techniques in a Complex Urban Environment(IEEE, 2010-09-10) Navarro Cadavid, AndresThis work presents results for a new method of ray tracing in urban environments using game engine and graphic processing unit (GPU). First advantage obtained with this method is the simplicity for 3D modeling from raster digital elevation model (DEM). Second advantage is the ability to precisely obtain ray parameters and the multiple paths interacting between transmitter and receiver in urban environment for high and low base station. A third advantage is the reduction in computing time by using the GPU capacity. In this paper, we show simulation results and compare them with measurements, obtaining a good fit. ©2010 IEEE.Ítem A statistical channel model for on body Area networks in Ultra Wide Band Communications(IEEE, 2009-09-10) Cardona, NarcisThis paper presents a novel statistical channel model for Ultra Wide Band Communications when On Body Area Networks Environments are considered. Results and Analysis of frequency measurements from 1GHz to 12GHz for body area networks are described. We propose a modified Saleh-Valenzuela statistical channel model considering different assumptions for small scale statistics in the model. Results show that the small scale amplitude follows a log normal distribution, the inter arrival times between multi path components are poisson process; the decay factor, the number of paths and clusters follow exponential distributions. The proposed model can be used for realistic simulations for on body communications in Ultra Wide Band systems. © 2009 IEEE.Ítem Performance evaluation of Vertical Handoff Algorithms(IEEE, 2010-10-10) Navarro Cadavid, AndresDifferent Vertical Handoff Algorithms (VHA) have been proposed in the literature recently. However, there is no consensus on how to evaluate performance of different VHA at the research community. Although some models have been proposed for evaluation of the VHA, this issue is a challenge because the VHA have evolved to become more sophisticated, thus the evaluation models must consider a variety of parameters. In this paper, we propose a new evaluation model for VHA that has been designed based on specific concepts taken from the multi-criteria evaluation and operational reliability. The proposed evaluation model allows analyzing VHA using measured values of some defined parameters, which can be obtained from simulating VHA on a network simulation tool. We present as a case study an evaluation of two VHA that shows the new model functionality and results. © 2010 IEEE.Ítem Análisis y caracterización de frameworks para detección de aplicaciones maliciosas en android(ResearchGate, 2014-06-01) Londoño, Sebastiany caracterización de frameworks para detección de aplicaciones maliciosas en Android. XIV Jornada Internacional de Seguridad Informática ACIS 2014 1 Resumen—Android incorpora distintos sistemas de seguridad para solucionar los problemas generados por aplicaciones malware como el modelo de permisos para cada aplicación, su propia plataforma de distribución de aplicaciones móviles "Google Play", entre otras. Pero existen otras alternativas que tienen como función mejorar la protección contra el software malicioso. En este artículo se presenta la información más reciente sobre metodologías, frameworks y sistemas que permiten resolver algunos de los problemas generados por aplicaciones maliciosas (Malware) para dispositivos móviles con sistema operativo Android.Ítem Measurement-based ray-tracing models calibration in urban environments(IEEE, 2012-07-08) Cardona, NarcisThis paper investigates the effect produced on the accuracy of the estimate of path loss in an outdoor environment in order to adjust the permittivity values for building wall, building roof and street floor by using a full 3D ray-tracing system. Due to the complexity of a real situation, estimation of path loss using the ray-tracing method is generally assumed one or three large classes of homogeneous materials to represent the building walls, building roofs and street floors in order have a viable model of the 3D environment. However, in a real case, an outdoor environment consists of many buildings and streets made of heterogeneous materials. We analyze the behavior of the statistical variation of standard deviation, correlation coefficient and the average error between the values of estimated and measured path loss data when considering various values of permittivity of these three classes.Ítem A 3D Game Tool for Mobile Networks Planning(IEEE, 2010-02-10) Madriñán, PatriciaIn this work, we show the concept of serious game applied to a 3D game for mobile planning. We combine the use of a traditional planning tool with a 3D game engine, representing propagation models as "avatars". The tool allows to execute an initial planning and also to "play" a game according to "missions" like perform a planning with a coverage objective.Ítem Prediction of Delay Spread Using Ray Tracing and Game Engine Based on Measurement(Institute of Electrical and Electronics Engineers Inc., 2015-05-11) Gomez, JorgeIn this paper, we show results of channel delay spread estimation using a 3D ray launching tool based on Game Engines and GPU, comparing simulation results with channel measurements of a MIMO system taken in Ilmenau. We show that the accuracy of the simulation is strongly affected by the ray angular separation in the first and second diffraction, obtaining a good fit between measurements and simulation.Ítem Game engines ray-tracing models for indoor channel modeling(IEEE, 2014-07-06) Cardona, NarcisThis paper investigates the use of a full 3D ray-tracing system based on Game Engine for the prediction of channel parameters in indoor using frequencies lower than usual. We explore the modeling of indoor channel for Digital TV frequencies and analyze the behavior of material on such low frequencies and how the frequencies affect the constitutive parameters of materials in the scenario. Because of the environment used for experimentation, the number of rays is very high and the number of interactions is higher than usual. We show results of the ray tracing model compared with measurements of delay spread at 594MHz.Ítem Análisis de Desempeño de Mecanismo de QoS en Redes Convergentes(ResearchGate, 2010-08-01) Cuellar Quiñones, Juan CarlosEn este trabajo se presenta el análisis de de resultados de una serie de simulaciones donde se analiza que mecanismo de QoS logra mantener dentro de valores admisibles los parámetros de calidad de servicio que presentan las recomendaciones Y.1540 y Y.1541 para la aplicación de voz, apoyados en un grupo de configuraciones realizadas en el núcleo de una red convergente con infraestructura MPLS.