June 05, 2019

Frequency Characteristics of Geometry-based Clusters in Indoor Hall Environment at SHF Bands

  • Fan W.
  • Hanpinitsak P.
  • Hejselbaek J.
  • Pedersen G.
  • Saito K.
  • Takada J.

This paper presents the analysis of geometry-based cluster frequency dependency at super high frequency (SHF) bands, which are 3, 10 and 28 GHz. Firstly, multipath components (MPCs) were extracted from the measured data by using space alternating generalized expectation maximization (SAGE) algorithm. Then, geometry-based clusters were estimated by using the enhanced scattering point based KPowerMeans (SPKPM) algorithm. Finally, the frequency dependencies of their scattering intensities (SIs) were discussed with the assistance of physical optics (PO). The analysis results showed that SPKPM could also be applied to mostly get reasonable scattering locations at multiple frequencies. Additionally, reflection on a smooth surface was the dominant mechanism of clusters where there were no frequency characteristics, whereas diffraction, scattering, and shadowing were significant causes of frequency characteristics. Assuming that the line-of-sight (LOS) is obstructed, diffraction, scattering, and shadowing accounted for 30-40 percent of the whole channel in terms of power which was not negligible and thus the channel was largely frequency dependent. The analysis results are expected to provide crucial insights for multiplefrequency channel modeling for the 5th generation (5G) wireless system.

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