宽带MIMO电力线系统有限反馈预编码方法

Limited feedback precoding method in broadband MIMO powerline communication system

多输入多输出(multiple-input multiple-output,MIMO)宽带电力线通信(power line communication,PLC)系统中由于电磁耦合存在共信道干扰,从而限制系统信道容量性能。针对该问题,提出一种基于量化反馈的预编码算法。利用两个相位角对预编码矩阵进行参数化,通过对相位角均匀量化形成预编码码本;再采用弦距离准则从码本中选取最优码字;最后基于数据流的子载波映射信息,提出一种新的功率分配方案。仿真结果表明,该算法利用码本索引可有效降低反馈开销,同时结合新的功率分配方案可有效降低系统误码率、提升系统吞吐量。

The co-channel interference from electromagnetic coupling limited the channel capacity performance of MIMO broadband PLC system.To solve this problem,this paper proposed a precoding algorithm based on quantitative feedback.Firstly,this method parameterized the precoding matrix by two phase angles,and generated the codebook by uniform quantization of the phase angles.Secondly,it selected the optimal codeword from the codebook by the chordal distance criteria.Finally,based on the tone map information of data streams,it proposed a new power allocation scheme.The simulation results show that the algorithm can effectively reduce the feedback overhead by the codebook index,and can further reduce the system bit error rate and improve the system throughput by the new power allocation scheme.