CAJ | 학술논문

无线信道传播效率是影响ETC系统性能的主要因素之一。考虑客车与轿车外形差异，定义了ETC系统信道传播损耗系数，提出一种基于两径模型的ETC系统信道传播损耗评估方法，便于评估ETC系统性能。评估方法预测及实测结果表明：ETC天线极化方式影响车载标签单元（OBU）接收功率，OBU距离地面高度越高，其接收功率越大；OBU识别范围小于10 m时，轿车引擎盖的电磁波反射引起垂直极化波衰减损耗突变，为保证OBU的成功识别，ETC天线距离地面高度应大于5．35 m。
무선신도전파효솔시영향ETC계통성능적주요인소지일。고필객차여교차외형차이，정의료ETC계통신도전파손모계수，제출일충기우량경모형적ETC계통신도전파손모평고방법，편우평고ETC계통성능。평고방법예측급실측결과표명：ETC천선겁화방식영향차재표첨단원（OBU）접수공솔，OBU거리지면고도월고，기접수공솔월대；OBU식별범위소우10 m시，교차인경개적전자파반사인기수직겁화파쇠감손모돌변，위보증OBU적성공식별，ETC천선거리지면고도응대우5．35 m。
The wireless channel transmission efficiency is one of the main factors affecting ETC system performance. Considering the shape difference between bus and car, channel transmission loss coefficient in ETC system was de-fined, and a propagation loss evaluation method for ETC systems based on two-ray model was proposed.Predicted and measurement results indicate that ETC antenna polarization mode influences on the received power of on board unit ( OBU) , the height OBU from ground more large, the received power more big.When the OBU recognition range is less than 10 m, because of the electromagnetic wave reflection of car hood, the vertical polarization wave attenuation loss is prone to sudden change.In order to ensure OBU is identified successfully in identified distance, the height ETC antenna from ground should be larger than 5.35 m.