天线阵结构对非视距室内MIMO信道容量的影响

采用2维射线跟踪法分析了非视距室内环境中天线间隔、天线阵形对MIMO系统容量和互补累积分布函数(CCDF)的影响。结果表明随着天线间隔减小，MIMO系统容量降低。10%中断容量表明，天线间隔相同时，有独立同分布瑞利信道容量大于线性阵容量大于方阵容量或者圆形阵容量的关系。当天线间隔大于等于3 时，不同天线阵列阵形对容量影响非常小，此时i.i.d.瑞利信道理论容量几乎全部实现。当天线间隔小于等于1 时，天线阵列阵形对容量影响较大，矩形阵和圆形阵MIMO系统容量相差较小，但都显著小于线性阵列系统容量。在非视距的室内环境中，要实现最大的MIMO容量增益，设计天线阵列时应该对天线间隔和阵列阵形综合考虑。

Antenna Array Structures Effect on Capacity of Indoor NLOS MIMO Channel

A 2-D shooting-and-bouncing ray-tracing (SBR) method is used to analyze the different antenna array structures effect on the capacity CCDF of indoor NLOS MIMO channel. The results show in NLOS indoor environments the less antenna interval is, the less MIMO channel capacities get. The results on 10% outage capacity show that there exist a fixed relationship that i.i.d Rayleigh channel capacity is larger than the capacity with linear antenna array which is larger than the capacity with rectangular antenna array or with circular antenna array. When antenna interval is equal to or larger than 3λ, antennas array structures affect the CCDF indistinctively and all the CCDF approach the theoretical i.i.d Rayleigh capacity, i.e. Telatar capacity. When antenna interval is equal to or less than 1λ, the CCDFS of MIMO system equipped with different antenna array structures changes remarkably. To obtain the MIMO capacity gains in indoor NLOS environment, antenna interval and antenna structure should be considered jointly when designing the antenna array.