Design of double codebook based on 3D dual-polarized channel for multiuser MIMO system

This paper proposes a precoding method based on double codebook for multiuser three-dimensional multiple-input multiple-output (3D MIMO) system deployed with dual-polarized antenna array. Considering the block diagonal feature of the transmit correlation matrix of 3D dual-polarized channel, we adopt the double codebook structure, where the precoding matrix is composed of an inner long-term matrix and an outer short-term matrix. Then, we introduce a set of 3D beams which possess good discrimination in horizontal and vertical domains to be the basic beam set and adopt a topology describing the 3D beam set to illustrate the angle information in an intuitive way. For the purpose of multiuser transmission, we also propose a corresponding limited channel information feedback scheme and a user scheduling criteria based on this double codebook structure. Simulation results demonstrate that the precoding method based on double codebook for the dual-polarized 3D MIMO system effectively improves system throughput compared with 2D transmission scheme.