提出了一种由新型Vivaldi天线单元构成的2×2十字交叉圆极化天线阵。Vivaldi天线单元采用边缘渐变对拓的锯齿结构, 提高了天线在4.7～7.0 GHz频带内的增益, 其反射系数低于-10 dB的带宽为2.4～11.0 GHz, 具有超宽带线极化特性。圆极化天线阵测量结果显示, 在4.5～7.0 GHz频带范围内, 其轴比均低于3 dB, 且整个频带范围内增益达11～13 dBi。

A circularly polarized (CP) crossed antenna array with 2×2 elements based on a novel antipodal Vivaldi antenna is proposed. The Vivaldi antenna with tapering serrated structure at the edges, which is a ultra-wideband (UWB) linearly polarized antenna, has a high gain at 4.7-7.0 GHz, and a wide impedance bandwidth of 2.4-11.0 GHz when the reflection coefficient is smaller than -10 dB. The measured data of the antenna array show that the axial ratio is lower than 3 dB between 4.5 GHz and 7.0 GHz. A high antenna gain from 11 dBi to 13 dBi is also achieved at the whole bandwidth of the array. The proposed antenna element and array both own UWB and high-gain characteristics.