Wireless channel characterization and modeling is the foundation of vehicular communication systems. However, most of the existing researches on vehicle-to-vehicle (V2V) channel are aimed at the traditional scenarios such as urban and suburban, and the researches on some complicated vehicular scenarios are insufficient. For example, little attention is paid to viaduct, tunnel, and cutting scenarios in vehicular communications, and these complex scenarios often become the high-incidence area of communication interruption, and then affect the overall performance of the vehicular communication system due to the bad and unique channel characteristics. In this paper, to fill this gap, time-varying characteristics of V2V channels in viaduct, tunnel, and cutting scenarios are investigated. Specifically, based on 5.9 GHz channel measurements, channel non-stationarity is quantitatively evaluated and compared. Further, a detailed analysis of time-varying power and delay of multipath components (MPCs) is presented. Based on the obtained results, the mechanism of physical environment affecting channel characteristics is analyzed, and the impacts of vehicular scenarios are quantified. Besides, the impacts of scenarios on the spatial distribution of MPCs are investigated. The angular distributions of MPCs in the three typical V2V scenarios are revealed, and the corresponding statistical characteristics are presented. Moreover, the characteristics of MPC clusters in different scenarios are further quantified and analyzed, such as MPC number in each cluster and cluster lifetime. It is revealed that the non-stationarity of the V2V channel originates from the birth-death process of MPC clusters, and the birth-death process is modeled statistically. The results in the paper show the V2V channel propagation mechanism and can be used for the design of vehicular communication systems in complicated scenarios.

中文翻译：

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复杂场景中的非固定车辆通道表征

无线信道表征和建模是车载通信系统的基础。然而，现有的车对车（V2V）渠道研究大多针对城市、郊区等传统场景，对一些复杂的车载场景的研究不足。例如，车载通信中很少关注高架桥、隧道、挖方等场景，而这些复杂的场景往往成为通信中断的高发区，进而由于不良和影响车载通信系统的整体性能。独特的渠道特性。在本文中，为了填补这一空白，研究了高架桥、隧道和切割场景中 V2V 通道的时变特性。具体来说，基于 5.9 GHz 信道测量，定量评估和比较信道非平稳性。此外，还详细分析了多径分量 (MPC) 的时变功率和延迟。基于所得结果，分析物理环境影响信道特性的机理，量化车载场景的影响。此外，还研究了情景对 MPC 空间分布的影响。揭示了三种典型 V2V 场景中 MPC 的角度分布，并给出了相应的统计特征。此外，进一步量化和分析了不同场景下MPC集群的特征，例如每个集群中的MPC数量和集群寿命。揭示了V2V通道的非平稳性源于MPC集群的生灭过程，并且对生死过程进行统计建模。论文结果展示了V2V信道传播机制，可用于复杂场景下的车载通信系统设计。