Double directional radio propagation measurements and radio channel modelling pertinent to mobile MIMO communications in microcells

摘要

Power spectra for AOAs in microcells are typified by a clustering of AOAs in multiple overlapping groups, which, when analysed as a single conglomeration, have large spreads. Centroids of such conglomerations are in the direction along street canyons towards the base station. Associated AOD spectra are markedly different, and have several distinct modes, with each mode, as well as the total spectra having smaller spreads than those of the AOA spectra. This, as well as evidence reported from scatter plots of AODs vs. AOAs, suggests deterministic behavior, in which AOD centroids change from street section to street section in accordance with street geometry with respect to a base station. It would therefore be very difficult to recommend a generic PAS model for AODs, although it is considered that this might be a possibility in the case of AOAs. The fact that multiple runs along many street sections resulted in very similar angular spectra also indicates that features of the built-environment dominate, and that variations due to different traffic situations are less significant than might be expected. Narrowband fading statistics can be modelled as Rician or Rayleigh, depending on the street section.