一种基于电调移相器的可重构天线

A Polarization Reconfigurable Antenna Based on Tunable Phase Shifter

设计并实现了一种基于反射式移相器的极化可重构天线。该天线使用一对交叉摆放的领结型振子作为辐射单元,并在馈电网络中通过两路移相器调整双馈端口间的相位差实现线极化、左旋圆极化和右旋圆极化模式之间的切换。通过加载匹配枝节的方法扩展了反射式移相器的移相范围,提高了移相器的移相精度,降低了天线圆极化模式带内的轴比。所设计天线的中心频率为5.4 GHz,在线极化模式下10 dB阻抗带宽为990 MHz,在圆极化模式下10 dB阻抗带宽分别为760 MHz和850 MHz,3 dB轴比带宽分别为510 MHz和480 MHz。该天线在频带内具有稳定的波束方向图,其平均增益为5.3 dB,并且具有27 dB的主极化-交叉极化隔离。最终的实测结果与仿真结果基本一致,表明该天线具有良好的性能。

A polarization reconfigurable antenna based on the reflective phase shifter is designed and implemented. The radiation element of this dual feed antenna is a pair of perpendicularly crossed bow-tie dipoles. In dual-feed network, the phase difference between two feed ports is adjusted through two phase shifters, to achieve left-hand circular polarization, right-hand circular polarization and linear polarization. Through the method of loading matching segments, the phase range of reflective phase shifter is extended and the phase accuracy of phase shifter is increased. The axial ratio of circular polarization can be improved through phase difference fine adjustment. The center frequency of this antenna is 5.4 GHz with measured 10 dB impedance bandwidth is 990 MHz, 760 MHz and 850 MHz in linear polarization, left hand circular polarization and right hand circular polarization, respectively. Moreover, the antenna maintains stable radiation patterns and the measured average gain is 5.3 dB with more than 27 dB polarization isolation. The measured results of this reconfigurable antenna are in good agreement with their simulated values.