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Ítem Adaptive planning of 3G/4G systems using Q-analysis or polyhedral dynamics(IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC, 2004-01-01) Cardona, NarcisIn this paper we present a method for use Q-analysis in the initial planning process and later dynamic adaptation for 3G/4G cellular systems that intends to balance load in order to maximize capacity and reduce lost and dropped calls independently of the type of service. We support our proposal on dynamic simulations made with an own developed tool for dynamic simulations of CDMA systems, and show initial results that partially probe our proposed method.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 analysis of scheduling algorithms in Next Generation Networks(IEEE, 2010-09-15) Cuellar Quiñones, Juan CarlosQoS in Convergent networks is widely discussed item in IP networks. But with the implementation of the Next Generation Networks by most operators around the world, QoS for different services and applications must fulfill. In order to deal with this problem, we simulate end to end QoS parameters, according to lTV Y.1540 and Y.1541 recommendations and different scheduling algorithms proposed by manufacturers and the literature. In this paper we show the results for such simulations for voice over IP service in different load conditions.Ítem Heuristic UTD coefficients applied for the channel characterization in an andean scenario(Institute of Electrical and Electronics Engineers Inc., 2015-07-19) Navarro Cadavid, AndresThis paper presents a comparison of three heuristic coefficients for the Uniform Theory of Diffraction (UTD), used to characterize the radiowave scattering in typical urban scenarios. The coefficients were implemented in a propagation model based on 3D ray-tracing techniques in an andean scenario. In order to evaluate each coefficient we analyze the statistical behavior of the mean and standard deviation of the absolute errors between the estimated values and the measured data of path loss in a large number of receptor points. Finally, we show the path loss prediction for each heuristic UTD coefficients proposed.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 Comunicaciones inalámbricas - 071 – evaluación de curso(Universidad Icesi, 2011-01-06T18:20:39Z) Universidad IcesiSe hicieron dos evaluaciones a lo largo del semestre. La primera consistió en una serie de mediciones de señal WiFi en la Universidad y su verificación con la herramienta WPS. Cada estudiante entregó un informe con las mediciones y el análisis estadístico de los resultados, de acuerdo a la predicción de la herramienta.Ítem Effect of terrain on electromagnetic propagation in urban environments on the Andean region, using the COST231-Walfisch-Ikegami model and GIS planning tools(IEE, 2003-03-31) Navarro Cadavid, AndresThis paper includes some results from a research project for the development of an electromagnetic propagation algorithm considering the influence of mountain terrain in UHF (300 MHz-3 GHz) band for wireless communications systems (i.e. 800-900 MHz in DAMPS/US-TDMA/IS-136 and GSM standard). The COST231-Walfisch-Ikegami (1988, 1991) model used in this work has been shown, together with Geographic Information System (GIS) and prediction tools for mobile propagation, to facilitate propagation studies, coverage analysis and analysis of main factors for cell planning in mobile systems. The basic concepts used to design the algorithm, the parameters used in measurements and results analysis in order to verify its applicability in cellular coverage prediction are described. Measurements have been done initially in Bucaramanga, a city located in the Andean Mountain system, for IS-136 band system. Coverage predictions have been done using a locally modified version of CellView, a GIS based Planning tool developed by the Universidad Politecnica de Valencia, while for the measurements a portable monitoring unit (i.e. Miniport Receiver EB200-Rohde&Schwarz from 10 kHz-3 GHz) was used.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.