Cluster-based analysis of 3D MIMO channel measurement in an urban environment

Massive MIMO (multiple - input - multiple - output) and full-dimensional MIMO systems in next-generation cellular communications systems as well as high-data-rate military systems have garnered considerable attention recently. For the assessment of their performance, knowledge of the 3D propagation channel characteristics, i.e., azimuth and elevation of the multipath components (MPCs) is essential. In this paper, we present first results of a 3D outdoor propagation channel measurement campaign performed in an urban macro-cellular environment. The measurements were performed with a 20 MHz wideband polarimetric MIMO channel sounder centered at 2.53 GHz. At each measurement location, parameters of all MPCs observed were extracted with RIMAX, an iterative maximum likelihood high-resolution algorithm. It was observed that MPCs naturally grouped into clusters. We then present a cluster-based analysis of the propagation channel providing some results of the intra and inter cluster parameters and their relevant statistics. Correlation between all extracted cluster parameters are also provided. Parameters such as elevation and azimuth spread (at the base-station) in this work have been used as input to recent international channel model standardization.