Vehicle-to-vehicle (V2V) communication is one of the promising communication applications designed to optimize traffic conditions and has played a crucial role in the improvement of intelligent transportation technologies. Since there is still some uncertainty regarding generalized models that provide a more accurate representation of propagation environments, the existing literature emphasizes the need for additional experimental studies in various countries and propagation environments. This study aims to investigate the low-density and high-density characteristics of V2V channels for highway, suburban, and urban propagation environments in Türkiye. Thus, first, channel measurements were conducted for all propagation scenarios. Then, after the estimation of path loss parameters, the best-fitted path loss model was determined for each propagation scenario by comparing log-distance, two-ray, and log-ray models. It was observed that the log-ray model offered remarkably better performance than the two-ray model, especially in the majority of scenarios with two-ray characteristics. In addition, small-scale modeling and shadowing were also examined, and the outcomes were compared to relevant literature. Last, generalized path loss models were developed for six propagation scenarios and compared with previous studies. Providing additional experimental data on the impact of traffic and road environments that vary across countries on the V2V channel, this study not only validated and compared existing propagation models but also improved the representing accuracy and generalizability of the newly proposed propagation models. Here, all findings were presented in detail to support the motivation of the research.

中文翻译：

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高速公路、郊区和城市环境中基于测量的 V2V 传播建模


车对车（V2V）通信是旨在优化交通条件的有前景的通信应用之一，在智能交通技术的改进中发挥了至关重要的作用。由于提供更准确地表示传播环境的广义模型仍然存在一些不确定性，现有文献强调需要在不同国家和传播环境中进行额外的实验研究。本研究旨在研究土耳其高速公路、郊区和城市传播环境中 V2V 信道的低密度和高密度特性。因此，首先，对所有传播场景进行信道测量。然后，在估计路径损耗参数后，通过比较对数距离、双射线和对数射线模型，确定每种传播场景的最佳拟合路径损耗模型。据观察，对数射线模型提供了比两射线模型明显更好的性能，特别是在大多数具有两射线特性的场景中。此外，还检查了小规模建模和阴影，并将结果与​​相关文献进行了比较。最后，针对六种传播场景开发了广义路径损耗模型，并与之前的研究进行了比较。这项研究提供了关于不同国家不同的交通和道路环境对V2V信道的影响的额外实验数据，不仅验证和比较了现有的传播模型，而且提高了新提出的传播模型的表示准确性和通用性。在这里，详细介绍了所有研究结果以支持研究的动机。