Vehicle to vehicle (V2V) communications using dedicated short-range communications (DSRC) are considered a promising technology for enhancing road safety. However, in V2V communications, passenger cars suffer from obstruction of bigger vehicles such as buses or trucks. Based on our measurement, a big vehicle can cause a signal loss from 10 to 15 dB due to shadowing. This results in a shorter communication range and reduces the safety message dissemination capability. In this paper, we analyze the impact of shadowing caused by multiple big vehicles on the V2V communication of passenger cars. We propose a model that takes into account both geometric and stochastic shadowing of multiple big vehicles. In order to cope with the physical size of vehicles and safety distance between them in the real world, we propose to use a repulsive point process called hardcore repulsive Poisson point process (PPP) to model the locations of vehicles. Generating procedure and some basic properties of this process are introduced. Based on the proposed model, we derive the average length of the shadow region and the shadowing loss caused by multiple big vehicles. We show that when the number of big vehicles increases from 10% to 80% of total vehicles in one lane, the shadow region increases from 50 m to 450 m on the road. Furthermore, the shadowing loss causes the relative number of cars within communication range of a typical car to reduce from 90% to between 15% and 50%, depending on whether the big vehicles are in the same or the adjacent lane of the consider car. We analyse the packet collision probability while taking into consideration the big vehicle shadow region and observe significant packet collisions without dedicated bus lanes.

中文翻译：

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大车阴影对车对车通信的影响

使用专用短程通信 (DSRC) 的车对车 (V2V) 通信被认为是提高道路安全的有前途的技术。然而，在 V2V 通信中，乘用车会受到较大车辆（如公共汽车或卡车）的阻碍。根据我们的测量，大型车辆可能会因阴影而导致 10 到 15 dB 的信号损失。这导致更短的通信范围并降低安全消息传播能力。在本文中，我们分析了多辆大型车辆造成的阴影对乘用车V2V通信的影响。我们提出了一个模型，该模型同时考虑了多个大型车辆的几何和随机阴影。为了应对现实世界中车辆的物理尺寸和车辆之间的安全距离，我们建议使用称为硬核排斥泊松点过程（PPP）的排斥点过程来模拟车辆的位置。介绍了该过程的生成过程和一些基本性质。基于所提出的模型，我们推导出阴影区域的平均长度和多辆大型车辆造成的阴影损失。我们表明，当一条车道上大型车辆的数量从总车辆数的 10% 增加到 80% 时，道路上的阴影区域从 50 m 增加到 450 m。此外，阴影损失导致典型汽车通信范围内的汽车相对数量从 90% 减少到 15% 到 50% 之间，具体取决于大型车辆是在考虑汽车的同一车道还是相邻车道。