MIMO信道相关性简化模型

Simplified model of mutual coupling correlation between antennas in MIMO channel

针对天线阵元相互独立与互相耦合的大规模多输入多输出(MIMO)信道模型,提出基于任意入射到达角(AoA)功率谱采样基函数的互耦与非互耦下的相关性简化模型,推导无互耦与考虑互耦效应下任意AoA功率谱的闭式表达式,以实测数据为基础,详细探讨有互耦与无互耦情况下的空域相关性与系统容量的变化趋势。仿真结果表明:互耦效应一方面对系统空间相关性有影响,会增加天线间的相关性;另一方面,选择合适的天线阵列及设置一定的阵元间距可以有效地提高系统容量,对实际设置天线阵列排列分布时具有参考意义。提出的表达式与理论结果具有良好的拟合效果,且可大幅度减少计算时间,提高计算运算效率,可以满足实际信道的设计要求。

Aiming at the massive multiple-input multiple-output(MIMO)channel model in which the antenna elements are mutually independent and mutually coupled,a simplified model of correlation between mutual coupling and non-coupling based on arbitrary incident angle of arrival(AoA)power spectrum sampling basis functions is proposed.A closed-form expression of the power spectrum of arbitrary incident AoA without mutual coupling and considering the effect of mutual coupling is derived.And the variation trend of spatial correlation and system capacity under the condition of mutual coupling and non-mutual coupling are discussed in detail.The simulation results show that,on the one hand,the mutual coupling effect has an impact on the spatial correlation of the system,which increases the correlation between antennas.On the other hand,the selection of appropriate antenna array and the setting a certain distance between array elements can effectively increase the system capacity which has a reference significance for the actual arrangement and distribution of antenna array.The proposed simplified model has a good fitting effect with the theoretical results.And it can greatly reduce the calculation time,improve the calculation efficiency and meet the design requirements of actual channels.