A broadband circular polarization antenna based on the composite structure of planar spiral and longitudinal helix is presented. Compared to single spiral antenna or helix antenna, proposed antenna has a better performance at low frequency by introducing two longitudinal helix arms connecting with the terminal of the planar spiral arms. As a result, the return loss, axial ratio (AR) and gain are both improved without increasing the antenna size. The antenna is designed to operate from 2 to 18 GHz and has a physical dimension of Φ 50×45 mm3. A prototype was fabricated and tested, the results show that the proposed antenna can provide an AR of less than 2.5 dB, a return loss of less than -15 dB and a gain of greater than 0.5 dBi.
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机译：提出了一种基于平面螺旋和纵向螺旋复合结构的宽带圆极化天线。与单螺旋天线或螺旋天线相比，通过引入两个与平面螺旋臂的端子连接的纵向螺旋臂，所提出的天线在低频下具有更好的性能。结果，在不增加天线尺寸的情况下，回波损耗，轴向比（AR）和增益都得到了改善。该天线的设计工作频率为2至18 GHz，物理尺寸为Φ50×45 mm
3
。制作并测试了原型，结果表明，所提出的天线可以提供小于2.5 dB的AR，小于-15 dB的回波损耗和大于0.5 dBi的增益。
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