宽带Ka波段平面反射阵列天线设计

Design of a broadband Ka-band reflectarray antenna

平面反射阵列天线的发展受到了带宽与功率容量两方面限制。为此,本文首先基于多谐振技术提出了一种新型平面反射阵列单元结构,相比于传统单元,所提出单元结构具有功率容量高、剖面低且相移曲线线性度好的特点。其次利用所提出单元,通过优化阵面特性在Ka波段设计了包含20×20个单元的平面反射阵列天线。最后利用电磁仿真软件进行模拟计算,结果显示在中心频点35 GHz处,天线峰值增益为27.58 dBi,口径效率为52.33%,副瓣小于−16.08 dB,并且在30.41~39.64 GHz频率范围内(相对带宽26.37%)天线增益跌落小于3 dB,并且所设计平面反射阵列天线最大功率容量可以达到13.99 MW,功率密度为218.54 W/mm^(2)。

The development of reflectarray antenna is limited by bandwidth and power capacity.In this paper,a novel reflectarray element based on multi-resonant technique is proposed firstly.Compared with the traditional element,the proposed element structure has the characteristics of high-power capacity,low profile,and good linearity of phase shift curve.Secondly,a reflectarray antenna with 20×20 elements is designed in Ka band by using the proposed element and optimizing the array characteristics.Finally,the electromagnetic simulation software is used to simulate the antenna,The results show that at the center frequency of 35 GHz,the peak gain of the antenna is 27.58 dB,the aperture efficiency is 52.33%,the sidelobe is less than−16.08 dB,and the antenna gain drop is less than 3 dB in the frequency range of 30.41−39.64 GHz(the relative bandwidth is 26.37%).Moreover,the power capacity of the designed reflectarray reaches 13.99 MW and the power density is 218.54 W/mm^(2).