| 摘要: |
| 在多用户下行多天线系统中，基站可利用信道状态信息将独立的数据流同时发送到
多个用户以得到更高的信道容量。由于在实际系统中基站很难实时得到各用户的完全信道状
态信息，可以基于有限的信道反馈量进行用户选择来提高系统的和速率。提出了一种部分信
道状态信息下利用有向图实现多用户下行多天线系统用户选择的算法。该算法将用户选择的
问题变成了在有向图中寻找闭合环的问题，可以大幅度降低用户选择的复杂度；克服了常
规的随机波束成形算法只有在用户数非常多的时候才能有效工作的弱点，在用户数少或中等
的时候能得到比其更好的性能。因此该算法更适合在实际系统中应用。 |
| 关键词: 多用户多天线系统 部分信道状态信息 用户选择 有向图 |
| DOI： |
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| 基金项目: |
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| Realization of User Selection Algorithm for Downlink Multiuser Multiple Antenna System with Directed Graph |
| ZHENG Hai-bo,ZHAO Li,LIU Ya-juan |
| (Qingdao Branch, Naval Aeronautical Engineering Academy, Qingdao 266041,China;Naval Flight Academy, Huludao 125001,China) |
| Abstract: |
| When channel state information（CSI） is available at the transmitter in down
link multiuser multiple antenna system, the base station can transmit independen
t data streams to multiple users simultaneously to achieve a much higher channel
capacity. Because of the fact that it is difficult for base station to obtain i
nstantaneous CSI exactly in practical system, partial CSI based user selection c
an increase system sum rate.In this paper a directed graph based user selection
algorithm is proposed for downlink multiuser mult
iple antenna system when the base station only knows users′ partial CSI. This a
lgorithm changes the user selection problem into problem o
f seeking closed loop in directed graph. It yields a considerable user selection
complexity reduction and overcomes the drawback of conventional random beamform
ing scheme which only enjoys significant gains with a large number of users. It
o
utperforms conventional random beamforming scheme when user number is small or m
oderate. This algorithm is easy to realize in practical systems. |
| Key words: multiuser multiple antenna system partial channel state information user selec
tion directed graph |
