Cluster-level parameters at 5.25 GHz indoor-to-outdoor and outdoor-to-indoor MIMO radio channels

This paper describes cluster-level results of indoor-to-outdoor and outdoor-to-indoor double-directional MIMO radio channel measurements carried out at 5.25 GHz. The measurements were performed using a wideband multi-antenna radio channel sounder. Using a set of several thousands of snapshots at the two reciprocal environments, we provide a useful insight into the channel for further channel modelling and channel simulations. We discuss the cluster azimuth spread, cluster delay spread, inter-cluster shadowing, number of clusters per snapshot, number of paths within the cluster, cluster birth rate and cluster lifetime. These parameters are presented for different scenarios by their statistical distributions, and also by their cross-correlation. The results show that both outdoor-to-indoor and indoor-to-outdoor scenarios behave very similar, so we suggest to merge these two cases.