大规模MIMO OFDMA下行系统能效资源分配算法

Energy-efficient resource allocation algorithm for massive MIMO OFDMA downlink system

针对大规模多输入多输出(MIMO)正交频分多址(OFDMA)下行移动通信系统,提出了一种基于能效最优的资源分配算法。所提算法在采用迫零(ZF)预编码的情况下,以最大化系统能效的下界为准则,同时考虑每个用户的最低速率要求,通过调整带宽分配、功率分配和基站天线数分配来优化能效函数。首先根据优化条件提出了一种迭代算法确定每个用户的带宽分配,然后利用分数规划的性质并采用凸优化方法,通过联合调整基站端的发射天线数和用户的发射功率来优化能效函数。仿真结果表明,所提算法在较少迭代次数的同时能够取得较好的系统能效性能和吞吐量性能。

An algorithm is proposed for energy-efficient resource allocation scheme in massive MIMO OFDMA downlink mobile communication system. A mathematical formulation of optimization issue is provided with the objective of maximizing system energy efficiency lower bound under the minimum data rate requirement of user, meanwhile the BS uses a zero-forcing（ZF） precoding. And then for optimizing energy efficiency function, the bandwidth allocation, power allocation and the number of antenna arrays at the BS are adjusted synchronously. First, an iterative algorithm derived from optimality condition for bandwidth assignment is proposed. Second, the properties of fractional programming and convex optimization are used to maximize the energy efficiency. Specifically, both the number of antenna arrays at the BS and the transmit data rate at the user are adjusted. Simulation results show that the proposed schemes not only have less iteration number but also have good perform for system energy efficiency and throughput.