反馈受限的多用户多输入多输出下行链路预编码算法研究

Research on Limited Feedback Precoding Algorithm of Multi-user Downlink MIMO System

在上行链路反馈受限的MIMO信道系统中,通过最大化反馈的信道质量信息可以获得相关门限阈值。现有研究在提高用户和速率方面已达到较好效果,但同时也提高了算法复杂度。为了在不损失多用户分集增益的前提下降低反馈开销,提出一种基于门限的次优下行链路预编码方案,在反馈信道方向信息(CDI)和信道质量信息(CQI)的基础上,应用迫零波束成形(ZFBF)算法进行预编码。实验结果表明,该算法在保证较高和速率的同时有效降低了计算复杂度。

In the uplink limited feedback system of MIMO, the related threshold can be got by maximizing the feedback channel quality information. Existing researches have achieved high sum rate, but also increased the algo rithm complexity. In order to reduce feedback overhead without losing user diversity gain, a suboptimal algorithm for downlink precoding is proposed. On the basis of the feedback channel direction information （CDI） and the channel quality information （CQI）, zeroforcing beamforming algorithm is applied to precoding. Simulation results show that the algorithm can ensure a relatively high rate and at the same time reduces the computational complexity effectively.