Abstract：Addressing the problem of maximizing the mutual information of MIMO channels with finite alphabet inputs, a low-complexity algorithm of linear precoding is designed. According to the mercury/water-filling theory, the algorithm integrates the precoding method based on the uniformly rotated Space-Time Linear Constellation Precoding (ST-LCP) matrix and the method of maximizing the minimum distance between output vector signals, where the one with higher mutual information is chosen for precoding. Then, in the precoding technique based on the uniformly rotated ST-LCP matrix, the singular value matrix of MIMO channels is selected to be the power allocation matrix, and two modifications are designed including the local search and the power addition on the singular value matrix. Finally, the computational cost of mutual information is further decreased by exploiting the symmetry of the finite alphabet set. The proposed algorithm obtains mutual information close to the theoretical maximum under various channel and SNR conditions, and reduces or even avoids search, resulting in much lower computational complexity. The simulation results verify the effectiveness of the proposed algorithm.
崔波, 刘璐, 金梁. 一种有限字符输入的线性预编码设计算法[J]. 电子与信息学报, 2014, 36(10): 2300-2306.
Cui Bo, Liu Lu, Jin Liang. An Algorithm for Linear Precoder Design with Finite Alphabet Inputs. , 2014, 36(10): 2300-2306.
2014, Vol. 36 
