Urban Radio Access Networks

The increase in demand for high-data rates on the move in the complex urbanenvironment requires either the allocation of new spectrum such as availablecontiguous spectrum in the mm-wave band or the use of novel configurationssuch as the application of massive multiple-input multiple-output (MIMO)technology. To enable the design of efficient wireless networks, an understandingof the propagation phenomena in the diverse urban environments isfundamental. In this chapter, we present results of studies related to fourthgeneration (4G) and future 5G radio systems both outdoor and outdoor-toindoor.Classifications include rural and highway, BS to pedestrian users,vehicular-to-vehicular, vehicular-to-infrastructure, container terminals, vegetation,and high-speed mobility such as trains. Results for path loss (PL)and shadow fading are presented from various studies of stochastic anddeterministic channel models based in outdoor, indoor-to-outdoor, hotspots,vehicular, and train environments. Relay stations and the impact of antennaplacement in vehicles, antenna terminal height, and the presence of pedestriansare discussed. Results of angular spread and rms delay spread of widebandchannels are presented for the frequency bands below 6 GHz allocated for4G networks, and preliminary results in the mm-wave band, envisaged for5G networks, including prediction of the impact of rain. To facilitate thesimulation of radio networks in urban environments the Hannover Scenariois proposed to give a common simulation environment