The increasing demand for more sensors inside vehicles pursues the intention of making vehicles more “intelligent”. In this context, the vision of fully connected and autonomous cars is becoming more tangible and will turn into a reality in the coming years. The use of these intelligent transport systems will allow the integration of efficient performance in terms of route control, fuel consumption, and traffic administration, among others. Future vehicle-to-everything (V2X) communication will require a wider bandwidth as well as lower latencies than current technologies can offer, to support high-constraint safety applications and data exhaustive information exchanges. To this end, recent investigations have proposed the adoption of the millimeter wave (mmWave) bands to achieve high throughput and low latencies. However, mmWave communications come with high constraints for implementation due to higher free-space losses, poor diffraction, poor signal penetration, among other channel impairments for these high-frequency bands. In this work, a V2X communication channel in the mmWave (28 GHz) band is analyzed by a combination of an empirical study and a deterministic simulation with an in-house 3D ray-launching algorithm. Multiple mmWave V2X links has been modeled for a complex heterogeneous urban scenario in order to capture and analyze different propagation phenomena, providing full volumetric estimation of frequency/power as well as time domain parameters. Large- and small-scale propagation parameters are obtained for a combination of different situations, taking into account the obstruction between the transceivers of vehicles of distinct sizes. These results can aid in the development of modeling techniques for the implementation of mmWave frequency bands in the vehicular context, with the capability of adapting to different scenario requirements in terms of network topology, user density, or transceiver location. The proposed methodology provides accurate wireless channel estimation within the complete volume of the scenario under analysis, considering detailed topological characteristics.

中文翻译：

---

城市环境中车辆通信的确定性 3D 射线发射毫米波信道表征。


人们对车内传感器的需求不断增加，追求的是让车辆变得更加“智能”。在此背景下，完全互联和自动驾驶汽车的愿景变得更加具体，并将在未来几年变成现实。这些智能交通系统的使用将能够在路线控制、燃料消耗和交通管理等方面整合高效的性能。未来的车联网 (V2X) 通信将需要比当前技术更宽的带宽和更低的延迟，以支持高约束安全应用和数据详尽的信息交换。为此，最近的研究建议采用毫米波（mmWave）频段来实现高吞吐量和低延迟。然而，由于较高的自由空间损耗、较差的衍射、较差的信号穿透力以及这些高频段的其他通道损伤，毫米波通信的实施面临着很高的限制。在这项工作中，通过将实证研究和确定性仿真与内部 3D 射线发射算法相结合，对毫米波 (28 GHz) 频段的 V2X 通信信道进行了分析。针对复杂的异构城市场景对多个毫米波 V2X 链路进行了建模，以便捕获和分析不同的传播现象，提供频率/功率以及时域参数的完整体积估计。考虑到不同尺寸车辆的收发器之间的障碍，针对不同情况的组合获得大尺度和小尺度传播参数。 这些结果有助于开发在车辆环境中实现毫米波频段的建模技术，并能够适应网络拓扑、用户密度或收发器位置方面的不同场景要求。所提出的方法在考虑详细的拓扑特征的情况下，在所分析的场景的整个范围内提供准确的无线信道估计。