基于粒子群算法的分布式MIMO系统圆形小区天线位置优化研究

本文研究分布式MIMO(Multiple-Input Multiple-Output)系统圆形小区基站侧天线端口的位置优化问题.论文首先建立了包含小尺度Nakagami衰落、阴影衰落和路径损耗的复合衰落信道模型,然后在收发端皆配置多根天线、移动台于小区内具任意概率分布、发射和接收端分别实施选择性传输和最大比合并方案下,在高信噪比条件下推导出圆形小区下行平均遍历容量的近似闭型表达式;随后通过对小区进行相应的区域预划分,采用粒子群算法而非传统遗传算法以快速搜索当前区域内天线端口的最佳位置,并最终根据小区天线端口位置的整体搜索结果确定天线优化布局.仿真结果表明,本文所推导的平均遍历容量近似表达式能较好地反映分布式MIMO系统性能,且所采用的基于粒子群算法的小区最优天线端口位置搜索结果也能较好地接近理论最佳位置.

Antenna Port Placement Optimization of Distributed MIMO System in Circular Cell Based on Particle Swarm Optimization

This paper focused its main research on the antenna port (AP) placement optimization of distributed multiple-input multiple-output (DMIMO) system in a circular cell.For this purpose, a composite channel model integrating with Nakagami-m fading, shadow fading, and path loss was established firstly;next, an approximate closed-form expression of downlink average cell ergodic capacity was deduced under the condition that high signal-to-noise ratio (SNR) was assumed, and multiple antennas were equipped at both the transmitter and receiver sides, which applied selective transmission (ST) and maximum ratio combining (MRC) schemes respectively, and moreover, the distribution of mobile station (MS) in the cell was arbitrary;then, a fast searching method based on particle swarm optimization (PSO) instead of traditional genetic algorithm was proposed to find the optimum positions of APs in the circular cell through dividing the cell into several predefined sections;and finally, the optimum APs' layout was provided according to the overall cell searching results.Computer simulation results show that, the approximate closed-form expression can exactly represent the performance of the DMIMO system, and the finally searched results of optimum AP positions in the cell based on PSO are very close to the theoretical antenna locations.