Characterization of Spatial Consistency of Cluster Channels in Urban Environments at 24 and 60 GHz

Currently, millimeter-wave (mm-wave) based wireless communications in the 30 to 300 GHz frequency band are attracting new attention because the existing frequency band below 6 GHz is very congested. In order to design and assess mm-wave systems, it is essential to characterize its propagation channel considering the spatial consistency (SC) for non-stationary user equipment. The 3GPP has proposed an SC procedure that provides spatial correlation to clusters for beam-tracking evaluation in dynamic scenarios. To characterize SC, the 3GPP follows only the LSP-dependent correlation distance, whereas this work proposed a parametric method to obtain a more reliable and accurate SC using cluster tracking, which provides a cluster visible region. This letter reports on the evaluation of SC of clusters in terms of cluster visible region based on the obtained measured data in two different mm-wave frequencies, 24 GHz and 60 GHz, in urban environments. The visible region is estimated by tracking the available clusters using the four-dimensional spatiotemporal multipath parameters: the departure/arrival angles (azimuth), delay time, and cluster power. The obtained visible regions for two different frequencies and scenarios are compared and confirmed the dependencies of SC of the clusters on frequency and environment.