Two-dimensional collaborative filtering approach to wireless channel characterization in medical complex scenarios

Abstract

Planning the deployment of antennas in complex environments is a difficult task that requires the analysis of each specific scenario. In many cases, real measurements are taken so as to map signal strengths, interferences, and so on. However, taking real measurements is very time consuming and becomes impractical in complex, large scenarios. With the aim to avoid this burden, simulation techniques based on Ray Tracing, combining Geometric Optics and Uniform Theory of Diffraction, are used to predict waves' behaviour within a given environment. Those simulations depend on a number of parameters, namely angular resolution, number of rebounds, cells size, etc. By tuning these parameters, high-definition (HD) and low-definition (LD) results can be obtained. Although more practical than manual measurements, the computational cost of simulations in HD prevents their use in complex environments and their LD counterparts are applied. In this article we propose a technique based on collaborative filtering (CF) that allows the use of LD simulations (with low computational cost) by lessening their low quality problems. The proposed CF strategy exploits spacial constraints in 2D propagation planes to improve simulation results, which end up being very similar to those of HD, with a fraction of its computational cost.