On the Application of Cylindrical Arrays for Massive MIMO in Cellular Systems

In this paper, the potential application of Uniform Circular Arrays (UCAs) instead of sectorized Uniform Planar Arrays (UPAs) in cellular deployments is studied. This includes fundamental observations on the aperture size observed by users. Furthermore, coverage trade-offs are investigated in terms of rate showing that with uniform user distributions the UCAs provides higher minimum rates while sacrificing peak rate compared to sectorized UPAs. Additional, the impact from sectorization, multiuser, and inter-sector interference is evaluated by numerical analysis. Finally, in order to enable the use of UCAs in standardization so called Array-Response-Matched (ARM) codebooks are proposed that can be constructed similar to the Discrete Fourier Transform (DFT) based codebooks currently used for UPAs. The construction and numerical evaluation of the ARM codebooks is also included in the paper.