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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 Delay spread control hiding first hit objects(2013-01-01) Navarro Cadavid, AndresThis paper proposes a methodology for the prediction and eventual cancellation of the main scatterer effects on broadcast radio channels. We assume the possibility of using absorbing material or paint to reduce the reflectivity of some surfaces and virtually 'hide' the scatterer, so as to control the maximum Delay Spread in terrestrial Digital Video Broadcasting systems. A desirable condition for the DVB-T2 operators is to limit the Delay Spread of radio channel in conditions where it is not possible to change the location or the orientation of the transmitting antenna; moreover, this can be useful to limit the Inter-Symbol Interference (ISI) and to improve the balance between the interleaving time and the channel capacity. In order to prove the applicability of object hiding, we used ray-tracing 3D techniques to identify the objects that can be hidden or camouflaged, and calculating the effect of objects on parameters of the DVB channel, in this case the delay spread. The results of the simulation applying physical hiding of object shown a expected reduction of Delay Spread. © 2013 EurAAP.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.