This paper proposes a trifrequency reconfigurable antenna (FRA), which can work in the X-band, Ku-band, and Ka-band, by controlling only two RF MEMS switches. The antenna element has a frequency ratio beyond 3 : 1 and provides a good candidate for the frequency reconfigurable antenna array, since the size of the antenna is reduced by loading multiple metal shorting holes between the antenna radiating surface and the ground plate, and the overall size is only 0.14λ_X × 0.35λ_X (λ_X is the free-space wavelength at 8.6 GHz). Based on the proposed FRA element, a 1 × 16 linear irregular frequency reconfigurable antenna array (FRAA) with beam deflection ability is designed, which effectively addresses the element spacing problem in the optimization of the array. In addition, the close-coupling in X-band and the grating lobe caused by the long distance of array element spacing in Ka-band are comprehensively considered. With uniform amplitude feeding network, the sidelobe level is below −15 dB under beam deflection. Moreover, both FRA elements and FRAA prototypes have been fabricated and measured to verify their superiority. Good agreements are obtained between simulated and measured results, which indicates that the antenna has potential application in the future multifrequency wireless communication and intelligent radar anti-interference fields.

中文翻译：

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具有X / Ku / Ka波段光束偏转能力的三频可重构线性不规则阵列

本文提出了一种三频可重构天线（FRA），只需控制两个RF MEMS开关即可在X波段，Ku波段和Ka波段工作。天线元件的频率比超过3：1，并且为频率可重构天线阵列提供了很好的候选者，因为通过在天线辐射表面和接地板之间以及整个天线之间安装多个金属短路孔可以减小天线的尺寸尺寸仅为0.14 λ _X  ×0.35 λ _X（λ _X是8.6 GHz的自由空间波长。基于提出的FRA元件，设计了一种具有波束偏转能力的1×16线性不规则频率可重构天线阵列（FRAA），有效地解决了阵列优化中的单元间距问题。此外，还综合考虑了X波段的紧密耦合和Ka波段中阵列元件间距的长距离引起的光栅波瓣。使用均匀的振幅馈送网络，在波束偏转下旁瓣电平低于-15 dB。此外，FRA元件和FRAA原型均已制作和测量以证明其优越性。在模拟结果和测量结果之间取得了良好的一致性，