Simulations and measurements of 15 and 28 GHz indoor channels with different array configurations

There are many different frequency bands above 6 GHz and into the mm-wave range above 30 GHz that are possible candidates for use in future 5G cellular systems. In this paper, we present some results for wireless channels at 15 and 28 GHz in an indoor scenario. The results are based on both measurements and ray tracing simulations. Basic comparisons of measured and simulated power-delay profiles, angle of departure and received power are presented to give an insight to the possibilities and limitations of utilizing ray tracing to characterize the indoor wireless channel at 15 and 28 GHz. We show that it is important to consider human body shadowing as well as finer structures and details in the ray tracing environment model in order to achieve reasonable results. Lastly, we also perform ray tracing simulations to assess the performance of a number of different array signal processing techniques, including beamforming, hybrid beamforming and spatial multiplexing.