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Combined Model for Outdoor to Indoor Radio Propagation

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In this paper, a new model used to compute the outdoor to indoor signal strength emitted by a base station is presented. This model is based on the combination of 2 existing models: IRLA (Intelligent Ray Launching), a 3D geometric-like model especially optimized for outdoor predictions, and MR-FDPF (Multi Resolution Frequency Domain ParFlow), a 2D FDTD-like model initially implemented for indoor propagation. The combination of these models implies the conversion of the ray launching signals on the border of the buildings, into virtual source flows that will be used as an input for the indoor model. The performance of the new combined model is evaluated via measurements, and it appears to be an efficient solution for radio network planning, both in term of accuracy and computational cost.
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... The application of such network in indoor area like office, factory or in outdoor or in vegetated creates different environment or channel model through which the communication path is set-up between the source and destination node. The appropriate modelling of the propagation channel and its elements is required to accomplish projects capable of attending the demands of different coverage areas (Roche et al., 2010;Alejos et al., 2012;Fernández and Cuiñas, 2013). Propagation loss is an important parameter to analyse the transmission range of the network. ...
... Path loss is defined as the difference between received and transmitted power. A MIMO channel with M transmitting and N receiving antennas, the power can be described by channel matrix (Roche et al., 2010). So, the path loss can be calculated as ...
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... In [20], the authors further combine the IRLA model with a FDTDlike method: MR-FDPF (Multi Resolution Frequency Domain ParFlow) [21] for an indoor to outdoor scenario where the accuracy was validated by the measurement campaign. In [22] and [23], the authors combine the IRLA model with MR-FDPF for outdoor to indoor scenarios. Based on the aforementioned work on the IRLA model [24], This article will contribute by providing: • Details on the calibration of the indoor materials. ...
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