ABSTRACT

A novel microstrip reflectarray antenna constructed by elements of random fragmented patches with square loops attached to the edge is proposed in this paper. The fragmented patch is gridded into 2 N × 2 N pixels, each of which is randomly assigned either conducting or non-conducting property. In this case, a variety of different reflection phases can be obtained due to the structural differences between the elements. To suppress the mutual coupling between elements, each fragmented unit is integrated with a metal square loop, and the reduction of the mutual coupling is indirectly analyzed across the frequency characteristics of the reflection phase for the combined elements. A prototype antenna with 7 × 7 elements was designed, fabricated, and measured. Both the simulation and measurement results show that the microstrip reflectarray antenna possesses a high gain of 19.7 dBi at its working frequency of 5.8 GHz, which is 2 dB higher than that of the reflectarray elements without square loops. Meanwhile, this antenna achieves an impedance bandwidth (|S| < − 10 dB) of 5.6%, side-lobes 13.1 dB below the main lobe, and with the cross-polarization level less than −18 dB.

摘要

本文提出了一种新型的微带反射阵列天线，该天线由随机碎片的单元组成，边缘带有方形环。零散的补丁被分成2 N×2 N个像素，每个像素都被随机分配为导电或非导电属性。在这种情况下，由于元件之间的结构差异，可以获得各种不同的反射相位。为了抑制元素之间的相互耦合，每个分段单元都与一个金属方环集成在一起，并且针对合并元素的反射相位的频率特性，间接分析了相互耦合的降低。设计，制造和测量了具有7×7元件的原型天线。仿真和测量结果均表明，微带反射阵列天线在5.8 GHz的工作频率下具有19.7 dBi的高增益，比不具有方形环路的反射阵列元件的增益高2 dB。同时，该天线的阻抗带宽（| S | <-10 dB）为5.6％，旁瓣在主瓣下方13.1 dB，并且交叉极化电平小于-18 dB。