阵列布局对机载MIMO信道容量影响

为进一步提高空地(air-to-ground,ATG)下行通信容量，建立了三维基于散射体分布的ATG MIMO单跳同心椭圆环信道模型，结合机载多入多出（multiple input multiple output，MIMO）均匀线阵以及圆阵布局方案，推导了基于阵列结构分量的机载MIMO信道相关矩阵，为通过合理设计机载MIMO天线结构来提升ATG传输速率，分析了阵列结构参数对遍历容量的影响。仿真表明，受ATG远距离通信影响，需要扩大天线间隔来提高MIMO信道容量，且相比于线阵布局，圆阵布局更加适应飞行姿态变化，获得较高的信道容量。 

The Effect of Array Structures on Airborne MIMO Channel Capacity

To improve the communication capacity of air-to-ground (ATG) downlinks, the three-dimensional geometrically based single bounce concentric elliptic ring scattering (GBSBCERS) channel model of ATG multiple input multiple output (MIMO) was set up. Combing with the linear array layout and circular array layout of airborne MIMO, the analytic formula of airborne MIMO channel correlation matrix and ergodic capacity was deduced based on array structures. Then the influence of array structures on the ergodic capacity was analyzed to improve the ATG transmission rate by means of antennas layout. The simulation results shown that the MIMO channel capacity will increase along with the increase of antenna distance in the influence of ATG remote communication, and the circular antenna layout which has more channel capacity than linear antenna layout can adapt to the UAV attitude change.