Hybrid Codebook Design for Multiuser MISO Systems with Limited Feedback

Multiuser MIMO (MU-MIMO) system with limited feedback can be divided into two classes generally. One is zero-forcing beamforming (ZFBF), and the other is per user unitary rate control (PU
²
RC) which is an extended technique of random beamforming (RBF). However, in order to perform well, ZFBF requires many feedback bits, and PU
²
RC requires many users. These drawbacks of the existing MU-MIMO systems limit system performance in real environment. In this paper, we propose a new MU-MISO system which has merits of two MU-MIMO schemes simultaneously. Simulation results show the new MU-MISO system has good performance with simple feedback and low complexity user selection.