用于ETC系统的超宽带宽圆极化天线设计  

Design of Ultra-wideband Circularly Polarized Antenna for ETC Systems

作　　者：叶笑辰 宋健 窦江玲 沈韬[1] 刘佳丽 YE Xiaochen;SONG Jian;DOU Jiangling;SHEN Tao;LIU Jiali(School of Information Engineering and Automation,Kunming University of Science and Technology,Kunming 650500,China;Beijing Institute of Mechanical Equipment,Beijing 100120,China)

机构地区：[1]昆明理工大学信息工程与自动化学院,昆明650500 [2]北京机械设备研究所,北京100120

出　　处：《微波学报》2024年第S1期44-47,共4页Journal of Microwaves

摘　　要：电子不停车收费(ETC)系统中存在跟车距离太近导致ETC系统无法识别下一辆车辆通行以及恶劣天气下使ETC识别不出车辆而造成放行失误。针对上述问题,设计了用于ETC系统的超宽带宽圆极化天线设计。为了保证ETC系统在恶劣天气下的接收功能,天线采用圆极化设计和高定向化。要实现圆极化设计,对辐射贴片进行切角,使辐射贴片表面的电流形成90°的相差,进而实现天线的圆极化特性。对4个辐射贴片进行旋转从而达到4个辐射贴片相位一致,使用同轴馈电将辐射贴片和旋转与相位补偿圆环单元进行连接,从而对轴比(axial ratio,AR)带宽的维持,以及阻抗带宽的提升。最终,以改进后的4单元作为天线的最优结果。通过仿真优化得到天线的各项性能,阻抗带宽为5.48~6.06GHz,AR带宽(小于3dB)的带宽处在工作频段内为5.5~5.875GHz,当θ=0°时,最大增益为9.6278dB且方向性最好。选定天线的最优结构,并进行实物加工和测量。实测结果表面,阻抗带宽为5.32~6.11GHz。该天线具有超宽带、圆极化、高定向的特点,为ETC系统提供了一种结构新颖的天线。In electronic toll collection(ETC)system,there are problems that the ETC system can not recognize the next vehicle passing because of too close following distance,as well as the bad weather makes the ETC not recognize the vehicle and cause the release error.To address the above problems,an ultra-wideband broad circularly polarized antenna is designed for ETC system.In order to ensure the reception function of ETC system in bad weather,the antenna adopts circular polarization design and high directionalization.To achieve the circularly polarized design,the radiating patch is cut at an angle so that the currents on the surface of the radiating patch form a 90°phase difference,which in turn achieves the circularly polarized characteristics of the antenna.The 4 radiating patches are rotated so that the 4 radiating patches are in phase,and the coaxial feed is used to connect the radiating patches and the rotating and phase-compensated circular units,which results in the maintenance of the axial ratio(AR)bandwidth and the enhancement of the impedance bandwidth.Finally,the improved 4 units are used as the optimum result of the antenna.The performance of the antenna is obtained through simulation optimization,the impedance bandwidth is 5.48~6.06 GHz,the bandwidth of AR bandwidth(less than 3 dB)is 5.5-5.875 GHz in the operating band,and whenθ=0°,the maximum gain is 9.6278 dB and the best directivity.The optimal structure of the antenna is selected and physically processed and measured.The measured results surface that the impedance bandwidth is 5.32~6.11 GHz.The antenna is characterized by ultra-wideband,circular polarization,and high directivity,which provides a novel structure antenna for ETC system.

关 键 词：超宽带 圆极化 高定向 微带天线 ETC 

分 类 号：TN821.1[电子电信—信息与通信工程] U495[交通运输工程—交通运输规划与管理]