高速动车组车载双频天线设计与布局研究

针对动车组内无线通信质量问题，在微带线的基础上运用分枝法，设计出满足高速列车车载要求的双频单极子天线。天线尺寸为23mm×36mm×1.3mm，最大增益为3.8dBi，其工作频段为2.28~2.64GHz和5.47~6.15GHz，在2.4GHz和5.8GHz频段相对带宽分别为14.6%和11.7%，覆盖ISM频段。以CRH380A型动车组内部环境为研究对象，运用CST电磁仿真软件，建立车厢内部车载天线布局仿真模型。同时，将车内传输效果与自由空间进行对比。各BSS内的天线传输系数在ISM频段内位于-20~-50dB之间，RSRP属于最优等级Ⅰ。验证了所设计天线的有效性及其布局的可靠性。研究结果对动车组车载天线设计以及车内天线布局有很好的参考价值。

The research on Design and Layout of On-board Dual-frequency Antenna for High speed train

Aiming at the quality of wireless communication in EMUs, a dual-frequency monopole antenna is designed based on microstrip line and branch method to meet the vehicle-mounted requirements of high-speed train. The size of the antenna is 23mm×36mm×1.3mm, the maximum gain is 3.8dBi, its working frequency band is 2.28~2.64GHz and 5.47~6.15GHz, the relative bandwidth in the 2.4GHz and 5.8GHz frequency bands is 14.6% and 11.7%, covering the ISM frequency band . Taking the internal environment of the CRH380A EMUs as the research object, using the CST electromagnetic simulation software, the simulation model of the vehicle-mounted antenna layout inside the carriage is established. At the same time, compared the transmission effect in the train with the free space. The antenna transmission coefficient in each BSS is between -20 and -50 dB in the ISM frequency band, and the RSRP belongs to the optimal level I. The effectiveness of the designed antenna and the reliability of its layout are verified. The research results have a good reference value for the design of the on-board antenna of the EMUs and the layout of the in-vehicle antenna.