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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 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 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 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 Comparison of heuristic UTD coefficients in an outdoor scenario(Institute of Electrical and Electronics Engineers Inc., 2013-05-15) Rego, Cassio G.This 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 for a Digital Video Broadcasting (DVB) service. 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 in an outdoor scenario.Ítem Indoor Propagation Using a Game Engine Ray-Based Model in Indoor Scenario at 5.4GHz(Institute of Electrical and Electronics Engineers Inc., 2016-05-15) Gimenez, Jordi JoanThe results of a simulation of signal propagation strength in indoor environment using a game engine ray-based tool and use of an open source 3D modeling tool for scenario building are presented in this paper, showing the flexibility of the XML description language for this kind of scenario. We show simulation results and compare them with an extensive set of measurements for an indoor scenario with multiple materials in the 5.4GHz band, obtaining a good match between the ray-based tool and measurements of received power. We found also that constitutive parameters have an important effect on the simulation results and made some small adjustments to improve results.