Measuring, modeling, and characterizing of indoor radio channel at 5.8 GHz

Wide-band indoor radio channel characterization for broadband radio access networks and Unlicensed National Information Infrastructure has been perfor med at 5.8 GHz, and results are given in this paper. Delay spreads of 8.8 a nd 17.2 ns and coherence bandwidths of 9.6 and 4 MHz have been found for li ne-of-sight (LoS) and obstructed line-of-sight (OLoS) situations, respectiv ely. Results have been compared with predictions made using a ray-tracing t ool, To get accurate predictions, a good description of the electromagnetic properties of the obstacles present in the environment is needed. Several experiments were made in order to characterize the electromagnetic paramete rs of six typical building materials, Transmission and reflection coefficie nts were measured using the free-space technique, A multiple successive int ernal reflection model was used to estimate the permittivity and conductivi ty by comparing the measured and predicted values of the coefficients. Seve ral samples of each material were measured, and the results vary from sampl e to sample, This variation has been characterized by the calculation of co nfidence bands for the parameters, The influence of both the dielectric par ameters and the order of reflections considered in the ray-tracing tool has been analyzed. The effect is reduced on narrow-band predictions but is mor e important on wide-band parameters as the delay spread, It is shown that t he measured delay spread cumulative distribution function falls within the band predicted using the measured maximum and minimum values of permittivit y.