基于双码本的多用户MIMO有限反馈预编码方法

Limited feedback precoding for multiuser MIMO systems based on double codebook

针对多用户多输入多输出(MIMO)下行链路由有限反馈导致的性能缺失,提出一种基于双码本的有限反馈预编码方法。该方法首先在接收端根据期望用户最大信干比准则从预置码本中选取预编码码字及扰动码字反馈给发送端,然后利用矩阵线性变换特性对预编码码字进行线性变换扰动以达到容量最优,从而补偿由于有限反馈导致的容量性能缺失。仿真结果表明,所提出的方法在保证反馈链路开销与系统误码性能的情况下,有效地改善了系统吞吐量。

Concerning the problem of performance loss due to limited feedback in muhiuser MIMO downlink systems, a new limited feedback precoding for muhiuser Multiple Input Multiple Output （MIMO） systems based on double codebook was proposed. The maximum SINR criteria was used for selecting optimal codeword from the Grassmannian codebook and perturbation codeword at the receiving, and feedback the Grassmannian precoding codeword index and perturbation codeword index to the transmitter, then the perturbation codeword was used at the transmitter to get optimal capacity, and compensating for the capacity performance loss due to the limited feedback. The simulation results show that the proposed method ensures Bit Error Rate （BER） performance and the cost of the feedback link, and the system throughput is improved effectively.