Large Scale Parameters and Double-Directional Characterization of Indoor Wideband Radio Multipath Channels at 11 GHz

This paper presents the large scale parameters of wideband multipath channels based on extensive measurement campaigns in various indoor environments. The measurements were conducted with a wideband multiple-input multiple-output (MIMO) channel sounder having a bandwidth of 400 MHz at 11 GHz which is a challenging frequency for future mobile systems. In particular, polarization characteristics of path-loss, shadowing, cross-polarization power ratio (XPR), delay spread and coherence bandwidth are characterized. The measurement results show that the path-loss exponents range between 2.0 and 3.0 for none-line-of-sight (NLoS), 0.36 and 1.5 for LoS, respectively. Vertically and horizontally polarized transmissions have almost same path-gain, but in some corridor-room NLoS environments, the path-loss for HH is significantly large. In most cases, the RMS delay spreads are less than 20 and 50 ns for NLoS and LoS, respectively, and the average coherence bandwidth is less than 30 MHz. The Rician K-factors range between 2 and 3 dB for cross-polarization, and in large Hall environments, those for co-polarization are greater than 6.0 dB with 10% probability. Finally, some dominant propagation mechanism and site-specific behaviors are illustrated using the double-directional measurement results.