Measurement-based angular characterization for 72 GHz propagation channels in indoor environments

In this paper, channel measurement campaigns at center frequency of 72 GHz with 2 GHz bandwidth conducted by Huawei company are introduced. The transmitter and receiver make use of similar horn antennas which are rotated step by step in the directional domains to capture the frequency spectra of spatial channels in line-of-sight and non-line-of-sight scenarios of indoor environments. The data is applied to extract the statistics of composite and cluster angular spreads in the azimuth and elevation of arrival. The variation of the angular spreads with respect to the distance between the transmitter and receiver is also investigated. A preliminary channel model is provided based on the analysis results. It is found that the directional dispersion of 72 GHz indoor channels is more sparse than those obtained in lower frequencies. The observations of less composite and cluster angular spreads imply that spatial beamforming techniques are preferable in either backhaul transmission cases or user-specific applications.