具有高选择性的滤波天线设计

Design of Filtering Antenna with High Selectivity

本文设计了一个具有高选择性的滤波天线.在基于1/4波长谐振器的二阶滤波器基础上,将末级谐振器用矩形贴片代替,并通过在馈线和矩形贴片之间引入一条新的耦合路径,使得滤波天线的增益通带两边产生两个辐射零点,有效地提高了天线的选择性,而且两个辐射零点的位置通过结构参数的调整可调.设计结果表明滤波天线工作在2.42 GHz,在反射系数<-10 dB的阻抗带宽为4.5%,在2.2 GHz和2.7 GHz处产生了两个辐射零点,有效地提高了选择性,而且该滤波天线具有低交叉极化的特性.

A filtering antenna with high selectivity is proposed.Based on the second-order filter using theλ/4,the final-stage resonator is replaced by a rectangular patch.Moreover,by introducing a new coupling path between feed line and rectangular patch,two radiation zeros,which effectively improve the selectivity of the antenna,appear at the both sides of the bandpass of gain,and the position of the two radiation zeros can be changed by adjusting the structure parameters.The design results show that the filtering antenna operates at 2.42 GHz,the impedance bandwidth of the reflection coefficient<-10 dB is 4.5%,and two radiation zeros are appeared at 2.2 GHz and 2.7 GHz,which effectively improves the selectivity.Moreover,the filtering antenna has low cross polarization.