基于射线跟踪的毫米波大规模天线车地间信道特性研究

Channel characteristic of millimeter wave massive MIMO under train-to-infrastructure scenario based on ray tracing method

以轨道交通列车地面间通信作为研究场景,毫米波大规模多天线信道作为研究对象,采用车厢接入点进行用户信息分发的方案,利用毫米波大规模天线波束赋形与空间复用技术与射线跟踪信道仿真,仿真了大规模多天线下,不同阵列和地面基站位置的接收功率、角度扩展,并列举了不同方案之间在传输速率上所存在的差别.通过对结果的分析,在轨道交通车地间通信场景下,毫米波频段散反射体一般存在于列车接入点周边;相比于阵列的垂直分辨率,更多的水平分辨率往往拥有更好的效果;更低的路径损耗与更广的覆盖范围不可兼得.研究成果将为轨道交通车地场景下毫米波大规模多天线系统的设计、评估及其在轨道交通中的应用、部署提供不可或缺的信道信息和理论依据.

In order to meet the strict requirements of next generation rail traffic wireless communication, millimeter wave train access point scheme and massive multiple-input multiple-output（MIMO） technique are proposed to achieve high-data-rate transmission on rail traffic scenarios. In the paper, we employ the deterministic ray-tracing channel model to simulate and analyze rail traffic train-to-infrastructure scenario. The received power, angular spread and transmission rate results are presented. In particular, we find that the horizontal resolution of large antenna array system has greater impact than vertical resolution and lower path loss and wider converge may not have both in millimeter wave train-to-infrastructure scenario. Finally, the simulation results imply that the influence of different scenarios should be evaluated when verifying millimeter wave massive MIMO for future rail traffic communications.