In this letter, we develop a three-dimensional (3-D) irregular-shaped semi-ellipsoid channel model for massive multiple-input multiple-output (MIMO) vehicle-to-vehicle (V2V) communication in street scattering environments. The geometric model is irregular-shaped due to the scattering environments cut by vertical structures along the roadside. With employing a uniform planar array (UPA), we first characterize the geometrical relationships between transmitter and receiver constrained by different boundaries of scattering regions in detail. Then we derive the closed-form expressions for the probability density functions (PDFs) of the angle of departure (AoD) and joint time of arrival (ToA)/AoD in azimuth and elevation planes. Moreover, we discuss the impacts of the street width and large-scale antenna array on channel statistical properties. Numerical results show that our proposed model can capture characteristics of massive MIMO V2V channels while in close agreement with the prior reported results, thereby demonstrating the efficiency of the proposed model that can provide guidance for system design and performance evaluation of massive MIMO V2V communication in street scattering environments.

中文翻译：

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街道散射环境中大规模 MIMO V2V 信道的新型 3-D 不规则形状模型

在这封信中，我们为街道散射环境中的大规模多输入多输出 (MIMO) 车对车 (V2V) 通信开发了一个三维 (3-D) 不规则形状的半椭圆体信道模型。由于路边垂直结构切割的散射环境，几何模型呈不规则形状。通过采用均匀平面阵列（UPA），我们首先详细描述了受不同散射区域边界约束的发射器和接收器之间的几何关系。然后，我们推导出方位角和仰角平面中离场角 (AoD) 和联合到达时间 (ToA)/AoD 的概率密度函数 (PDF) 的闭式表达式。此外，我们讨论了街道宽度和大规模天线阵列对信道统计特性的影响。