一种基于码本轮转的有限反馈量化方法

A Finite Feedback Quantization Method Based on Codebook Rotation

大规模多输入多输出(Multiple-Input Multiple-Output,MIMO)系统中随着天线数目的增加,其反馈比特数将随之大幅度增加。为此,提出了一种基于码本轮转的有限反馈量化方法。该方法中,用户在前一时刻得到最佳码字之后,在码本中选取轮转区域构成虚拟码本,判断当前时刻的信道向量,满足轮转条件的用户将虚拟码本轮转到码本起始位置,在虚拟码本中进行量化;不满足轮转条件的用户在原始码本中进行量化,选出当前时刻的最优码字。反馈比特数分析与仿真结果表明,所提方法可轮转的虚拟码本减少了量化码字的数量,从而减少了反馈比特数,是系统性能与反馈比特数的一种折中。

As the number of antennas in a massive multiple-input multiple-output(MIMO)system increases,the number of feedback bits will increase significantly.For this problem,a limited feedback quantization method based on codebook rotation is proposed.In this method,after the user obtains the best codeword at the previous moment,the user selects the rotation area in the codebook to form a virtual codebook,determines the channel vector at the current time,and the user who meets the rotation condition rotates the virtual codebook to the start of the codebook and the position is quantized in the virtual codebook.Users who do not meet the rotation conditions are quantified in the original codebook to select the optimal codeword at the current moment.The feedback bit number analysis and simulation results show that the proposed method can rotate the virtual codebook to reduce the number of quantized codewords,thereby reducing the number of feedback bits,which is a compromise between system performance and number of feedback bits.