用于MIMO广播信道的带多波束选择的正交随机波束成形算法

本文提出一种基于有限反馈的波束和用户选择方案,在这种方案中,用户端利用一个随机正交码本对其信道方向信息(CDI)进行量化,计算其最大信号与干扰加噪声功率比(SINR),并把这些信息反馈给基站;基站根据接收到的这些反馈信息,按照和容量最大的准则选择出多个正交波束以及相应的多个用户.和sharif等人最近提出的方案相比,我们提出的方案能根据系统参数,如用户数和信噪比(SNR),对选择的波束成形矢量及其对应的用户的数量和集合进行调整,当用户数量较小时,和容量性能得到了很大的提升,同时避免了选择波束成形矢量时的用户冲突,另外,基站也不需要广播波束成形矢量给各个用户.

Random Orthogonal Beamforming with Multi-beam Selection for MIMO Broadcast Channel

In this paper,we propese a beam and user selection scheme that is enabled by feedback of quantized channel state in- formation.In this approach,each user quantize its channel direction information with a codebook,calculate its maximum signal-to-inter- ference-plus-noise-ratio (SINR) and then feedback these information to the base station;the base station selects one set of orthogonal beamforming vectors and the associated users for downlink transmission such that the throughput is maximized based on the these feed- back information.Compared with the recently proposed scheme by Sharif et al.,the present scheme can adjust the number and the set of beams and the associated users according to system parameters,such as the number of users and signal-to-noise-ratio (SNR),to achieve higher downlink throughput when the number of users is not large.In addition,our scheme avoids multi-user conflicts when selecting beamforming vectors,and requires no broadcast of beanrforming vectors.