复杂场景下的ETC系统路径损耗研究

Research on ETC system path losses in complicated scenes

无线信道的路径损耗是影响电子不停车收费(ETC)系统传播效率的最大因素。考虑在多车道情形下,周围的复杂环境都会引起电磁波在信道中的传播损耗,因此分析了多径射线波的几何特征,提出一种ETC系统的信道传播损耗模型。通过对比讨论旁道大型车辆以及前方地面或引擎盖引起的路径损耗对系统的影响,得出旁道车辆引起的绕射路径和前方地面或引擎盖引起的反射路径是影响系统信道传播的主要因素。对于特定场景的仿真结果可以得出:当旁道车辆与路侧单元(RSU)的距离为0. 6 m且被识别车辆与路侧单元(RSU)的距离越小时,系统的路径损耗越小。

The path loss of wireless channel is the biggest factor affecting transmission efficiency of the electronic toll collection(ETC)system.Considering that the complex surrounding environment will cause electromagnetic wave propagation loss in the channel under the condition of multi-lane,a channel propagation loss model of ETC system by analyzing the geometric characteristics of multipath radiation is proposed.The influence of the path loss caused by the bypass large vehicle and the front ground or the engine hood is discussed.The diffraction path caused by the bypass vehicle and the reflection path caused by the front ground or the hood are the main factors influencing the system channel propagation factor.The simulation results of the specific scenario can be drawn as follows:when the distance between bypass vehicle and road side unit(RSU)is 0.6 m and the distance between identified vehicle and road side unit(RSU)is smaller,the system path loss is smaller.