一种小型化树杈形缝隙Vivaldi天线的设计

设计了一种3.4~7.6 GHz频段的超宽带高增益低交叉极化的小型化Vivaldi天线。该天线是在传统Vivaldi天线基础上引入树杈形缝隙结构设计而成的新型Vivaldi天线。通过在辐射片引入树杈形开缝结构,改善了天线表面的电流,使其汇聚于缝隙附近,从而提高天线的辐射性能,改善天线的阻抗匹配特性,展宽天线带宽。仿真结果表明该小型天线在3.4~7.6GHz的频率范围内驻波比小于2,以5.4 GHz为中心频点的有效带宽达到4 GHz,在中心频点5.4 GHz增益为6.2 d B且交叉极化低于-20 d B。天线的尺寸仅为30 mm×30 mm。在此基础上加工并制作了天线样件,实测结果和仿真吻合良好,可以应用于无线通信系统中。

Design of a Miniaturized Vivaldi Antenna with Fork Type Slot

A high gain and low cross polarization ultra-wideband Vivaldi antenna was designed, and its frequency band was 3.4-7.6GHz. A new fork type slot structure was proposed based on the traditional Vivaldi antenna. By adopting fork type slots on the radiation surface, the surface current of this antenna was modified and converges around the gap, so its radiation property was enhanced. The impedance match feature was also improved and the bandwidth was widened. Within the 3.4-7.6GHz frequency band, the measured VSWR is lower than 2, the effective bandwidth reaches 4GHz with its center frequency 5.4GHz. The gain is 6.2dB at the center frequency 5.4GHz and the cross polarization is lower than -20dB. The size of the antenna is only 30mm*30mm. The antenna prototype was fabricated and the S parameters as well as antenna pattern were measured. The results are in good agreement with the simulations. The antenna can be applied in wireless communication system.