一种降低信息反馈的分布式MIMO系统下行波束成形

Beamforming Scheme with Low Information Feedback for Distributed MIMO Downlink Systems

分布式多输入多输出(MIMO)系统可以利用不同基站的多天线进行空分复用,使系统的容量和性能得到提高,但是在闭环的传输过程中需要向用户反馈解码矩阵,消耗了系统的资源。提出了一种利用对用户信道矩阵斜投影的预编码方法,可以降低基站到移动用户的信息反馈量,并且有效地消除了多用户间的共信道干扰,与迫零的预编码方法相比,可以使系统的误比特率性能和系统的容量得到改善。仿真实验验证了所提方法的有效性。

In distributed multiple-input multiple-output（MIMO） systems, using multiple antennas in different base stations, capacity and performance of the system can be improved through spatial division multiplexing. However, in a closed loop transmission process, base stations have to feedback decoding matrixes to the mobile stations, and then to consume resources of the system. In this paper, an oblique projected method is proposed based on a channel matrix. The proposed method can reduce the quantity of information needed to be sent back to mobile stations from the base stations, and thus effectively suppresses interference from other mobile stations. Compared to the zero-forcing method, the proposed method can improve the system＇s bit-error-ratio performance and capacity. Simulations show effectiveness of the method.