一种新型极化捷变有源微带天线阵

本文提出了一种新颖的极化捷变放大器型有源微带天线阵,只要在馈电端电控单一有源电路就能实现整个微带天线面阵极化的捷变和信号的放大.利用角馈方形微带贴片设计了一副具有高隔离度和低交叉极化的新颖16元双极化面阵,并分析了天线阵的共极化和交叉极化方向图.介绍了有源电路的设计.该电路利用一专用电控移相器,通过改变场效应管(FET)栅极的直流控制电压,电控两极化端口间的0°或90°相差,实现天线阵由线极化到圆极化的捷变.低噪声放大器(LNA)不仅使有源天线增益提高12-14dB,而且改善了天线的驻波比带宽和隔离度.文中给出了无源双极化阵和有源阵的实验结果,证实了理论的有效性.

A Novel Polarization-Agile Active Microstrip Antenna Array

A novel polarization-agile amplifier-type active microstrip array is proposed,in which the polarization agility and amplification of signal for the whole microstrip antenna array can be realized by electrically controlling one active circuit only.Using corner-fed square patch element,a new 16 element dual-polarized array with high isolation and low cross-polarization is designed.Its co-and cross-polarization radiation patterns are analyzed.The design method of active circuit is introduced,in which by changing the gate voltage of FET of a phase shifter,0°or 90°phase shift between dual ports is electrically controlled,resulting in the agility from the linear to circular polarization.The LNA enhances the active gain by 12-14dB,and improves the VSWR bandwidth and the isolation of the antenna as well.The experimental comparisons between passive dual-polarized arrays and active arrays are presented to verify the theory.