Increasing the sum-throughput of cells with a sectorization method for massive MIMO

In massive multiple-input multiple-output time division duplex systems, the number of users simultaneously served by the base station (BS) is heavily limited if uplink orthogonal pilots are used. This difficulty can be alleviated by introducing non-orthogonal pilots through exploiting second-order channel statistics and sectorization. In this paper, we consider the large uniform linear array and propose a novel sectorization method with low complexity, in which multiple users per sector can be simultaneously served as if there were multiple BS antennas with identical directional characteristics in each sector. Numerical results show that the sum-throughput can be greatly increased compared to the typical massive MIMO architecture.