MIMO系统一种新的功率分配算法及容量分析

A Novel Power Allocation Algorithm for MIMO Systems and Capacity Analysis

在不额外增加发射功率和带宽消耗的情况下,注水功率分配算法能够获得最大的多输入多输出(MI-MO)系统容量.基于拉格朗日乘数法,推导给出了MIMO系统注水功率分配算法的显式解.利用信道冲激响应矩阵的奇异值分解(SVD)算法,推导给出了注水功率分配算法MIMO系统的容量分析公式.利用数字波束形成(DBF)技术,提出了一种新的功率分配算法,推导给出了该算法MIMO系统的容量分析公式.仿真结果表明,提出的功率分配算法的系统容量虽然略低于注水功率分配算法的系统容量,但它的计算复杂度较低.

The water-filling power allocation algorithm can achieve the maximal capacity of multiple-input multiple-output （MIMO） systems with no additional power and bandwidth consumption. Based on Lagrange method, the explicit expression of the water-filling power allocation algorithm for MIMO systems is derived. With the singular value decomposition （SVD） algorithm to the channel impulse response matrix, the capacity analytical equation is derived for MIMO systems with the water-filling power allocation algorithm. Employing the digital beam-forming （DBF） technique, a novel power allocation algorithm is proposed and the capacity equation for MIMO systems with this algorithm is derived. Simulation results show that although the capacity of systems with the proposed power allocation algorithm is slightly smaller than that of systems with the water-filling power allocation algorithm,its computational complexity is lower.