Abstract: In traditional distributed Multiple Input Multiple Output(MIMO) system, the transmitting power is not allowed to be shared among antennas. To deal with this problem, capacity-optimal precede with per-antenna power-constrained is discussed. The optimization problem is solved by Lagrange dual optimizing procedures, the correlative algorithms and the signal emission strategy under different antenna configuration and capacity criterion are given. Simulation results indicate that the numerical capacity-optimal preceding enhances the channel capacity, compared with that of sub-optimal solution when the number of transmit antennas is more than that of receive antennas, or when the channel matrix is rank-deficient.

Key words: Multiple Input Multiple Output(MIMO), precoding, channel capacity, power-constrained, dual function, optimal transmission

摘要： 针对分布式多入多出(MIMO)系统各天线功率无法共享的问题，基于分布式MIMO系统各天线功率受限的假设，提出容量准则下的最优预编码矩阵设计方案。采用Lagrange对偶优化的方法，将原优化问题转化为其对偶问题，给出求解预编码矩阵的迭代算法流程，以及在不同天线配置和容量准则下的信号发射策略。仿真结果表明，在发射天线数目多于接收天线数目时或信道矩阵缺秩时，该迭代算法求得的预编码矩阵的容量性能优于已有次优解析解。

关键词: 多入多出, 预编码, 信道容量, 功率受限, 对偶函数, 最优发射

CLC Number: 

• TN929.5