一种新型单层微带反射阵列设计

Design of a Novel Single-Layer Microstrip Reflectarray

设计了一个工作于X波段的单层微带反射阵列天线,阵列单元采用双方环与方形金属贴片组合结构,通过调整内侧方环的长度可以实现超过360°的移相范围。选择角锥喇叭天线作为微带反射阵列的馈源。为了获得宽带特性,阵元间距选择约1/4中心频率波长。利用高频电磁仿真软件Ansoft HFSS对所设计的反射阵列进行建模仿真,结果表明:反射阵列在中心频点处的增益为20.5 dB,1 dB增益相对带宽达到20.9%。在此基础上调整阵元尺寸,使得反射阵列主波束分别指向φ= 0°,θ= 30°和φ= 0°,θ=-45°方向。所设计的反射阵列具有频带宽、增益高、可设定主波束指向的优点。

A single-layer microstrip reflectarray antenna for X band is designed. The element in the reflectarray is made of two metal square rings and a metal square patch. It provides a more than 360° linear phase range by adjusting the length of the inner square ring. The reflectarray is fed by a horn. The broadband characteristic of the reflectarray is obtained due to about a quarter central frequency wavelength of the element space. High frequency electromagnetic simulation software Ansoft high frequency structure simulator (HFSS) is used to model and simulate the reflectarray. The results show that the gain of the reflectarray at the central frequency is 20.5 dB,1 dB gain relative bandwidth reaches 20.9%,and the main beam can point to φ=0°,θ=30° and φ=0°,θ=-45° by adjusting the size of array elements. So, the reflectarray designed has the advantages of wide bandwidth, high gain and beam orientation.