MU-MIMO transmission by beam selection at user terminals

摘要

Multi-user MIMO (MU-MIMO) improves the system channel capacity by employing the transmission between a base station and multiple user terminals (UT). Block Diagonalization (BD) has been proposed in order to realize MU-MIMO downlink. The BD algorithm cancels inter-user interference by creating the weights so that the channel matrixes for the other users are set to be zero matrixes. However, when the number of transmit antennas is equals to the total number of received antennas, the transmission rate by the BD algorithm is decreased. In this report, we propose a beam selection method to reduce the number of nulls for the other users except an intended user by the BD algorithm. It is verified that the proposed method dramatically improved the Bit Error Rate compared to the conventional BD algorithm, regardless of the bit rate and number of users.