A Consideration on An Improved User Selection Algorithm in Multiuser MIMO Broadcast

摘要

In multiuser MIMO-BC (Multiple-Input Multiple-Output Broadcasting) systems, user selection is important to achieve multiuser diversity. To achieve this multiuser diversity with a small amount of calculation, we have proposed an improved user selection algorithm in an earlier report, referred to as user re-selection based on spatial orthogonality (URSO), the URSO algorithm achieves higher sum rate capacity than the SUS (Semiorthogonal User Selection) algorithm. Although some studies have been made on the earlier report, what seems to be lacking is the study about calculation complexity and setting of the algorithm threshold. In this report we evaluate the calculation complexity of URSO algorithm by using the amount of complex multiplications as parameters. We also evaluate the execution threshold parameter of the URSO algorithm. We show that the URSO algorithm has a calculation complexity almost equal to that of the SUS algorithm and they are much lower than that of the optimal user selection algorithm.