Numerical Modeling of the Effect of the Built Environment and Usages on Downlink EMF Exposure Induced by MU-MIMO 5G Antennas

In this paper we use numerical modeling to assess exposure to a MU-MIMO 5G antenna in different built environments. First, users are randomly distributed inside and outside buildings, and the channel between the antenna elements and the users is computed using ray-tracing. Second, beamforming is computed using zero-forcing method to maximize the throughput to serve users. The process is iterated until all users have been served. By taking into account usages, this leads to a time dependant radiation pattern of the antenna. This pattern is used to compute exposure maps with a ray-tracing method. These maps can be averaged over time to outline the influence of the environment on the spatial distribution of the electric field level.