39.5 GHz室内走廊环境毫米波MIMO信道特性研究

Investigation of 39.5 GHz mm-wave MIMO channel characterization for a corridor environment

目前5 G采用毫米波通信系统,其中39.5 GHz频段为其中关键使用频段需要研究其MIMO信道特性。采用射线跟踪法预测在走廊环境下的39.5 GHz毫米波MIMO信道特性,通过对比仿真和实测结果验证了射线跟踪法的可行性。发现路径损耗斜率较小,说明该环境下毫米波传输较远。同时发现了沿走廊纵向方向收发距离较近时,以直射径为主,LOS分量大,距离较远时有效反射次数较少,角度扩展小相关性强,LOS分量也大,而沿纵向方向中间处具有丰富的散射,NLOS分量增大,所以容量会出现峰值。在此基础上预测了走廊环境下不同区域的2×2、4×4 MIMO以及4×64 Massive MIMO信道容量变化,发现了走廊中间的信道容量高于走廊壁两侧,同时发现采用4×64 Massive MIMO相较于4×4 MIMO可以获得一定的容量增益,但是不会有巨大的提升。

The millimeter wave communication system is used in 5 G, and the 39.5 GHz band as a key use band needs to study its MIMO channel characteristics. The characteristics of 39.5 GHz millimeter-wave MIMO channel in corridor environment are predicted by ray tracing method. The feasibility of ray tracing method is verified by comparison simulation and measured results. It is found that the path loss slope is small, indicating that the millimeter wave transmission is far away in this environment. At the same time, it is found that when the transmission and reception distance is relatively close along the longitudinal direction of the corridor, the direct path is dominant, the LOS component is large, the effective reflection times are small when the distance is long, the angle expansion is small, the LOS component is large, and the LOS component is large. There is a lot of scattering, and the NLOS component increases, so the capacity will peak. Based on this, the capacity changes of 2×2, 4×4 MIMO and 4×64 Massive MIMO channels in different areas of the corridor environment are predicted. It is found that the channel capacity in the middle of the corridor is higher than that on both sides of the corridor wall, and it is found that 4×64 Massive MIMO can achieve certain capacity gain compared to 4×4 MIMO, but there won′t be a huge boost.