Determinant-based MIMO scheduling with reduced pilot overhead

作者：Ko Kyeongjun; Lee Jungwoo^*

来源：EURASIP Journal on Wireless Communications and Networking, 2012, 1-10.

DOI：10.1186/1687-1499-2012-71

In a multiuser multiple-input multiple-output (MU-MIMO) cellular system where there are many candidate users, it is critical to select a user group which maximizes the overall throughput of the system. However, the optimal scheduling strategy (exhaustive user selection) is computationally prohibitive when the total number of users is large. In this article, we propose a determinant-based user selection algorithm which reduces the search complexity without much performance degradation. A key contribution of this article is to use a matrix determinant as a measure of orthogonality as well as channel quality in user selection. Linear precoding schemes (zero-forcing beamforming or block diagonalization) widely used in MU-MIMO systems require two sets of pilots to estimate both raw and effective channels, which results in increased pilot overhead. In order to reduce the overhead, we also propose a new pilot scheme with only one set of pilot, which is another key contribution of this article. The new pilot scheme is combined with the proposed scheduling algorithm. Simulation results show that the proposed scheduling algorithm with a new pilot scheme reduces computational complexity and pilot overhead with negligible performance degradation compared to the exhaustive scheduling with a conventional pilot scheme.

• 出版日期2012