双模态涡旋电磁波阵列天线设计

Design of A Dual-Modal Vortex Electromagnetic Wave Array Antenna

为了提高频谱利用率,设计了一种可生成l=+1和l=-2两种模态的轨道角动量涡旋电磁波阵列天线.阵列天线由两组辐射贴片与功分相移馈电网络组成,功分相移馈电网络为每组阵列天线依次提供相等幅度和恒定相位增量的信号,从而生成不同模式的OAM涡旋波.通过合理调节两个馈电网络的相位,使得两个微带天线阵生成l=+1和l=-2的轨道角动量涡旋电磁波,由于辐射阵元之间相互耦合,阵列天线获得了比较宽的带宽.测试结果表明,两个阵列天线的阻抗带宽分别达到780 MHz和610 MHz,两端口之间的隔离度大于32.5 dB.

In order to improve the spectral efficiency,an array antenna which can generate orbital angular momentum(OAM)vortex electromagnetic waves in l=+1 and l=-2 mode is proposed.The proposed antenna arrays are composed of two groups radiation patchs and power division phase shifting feed networks,which provide equal amplitude and constant phase difference for each group of array antenna.Then OAM vortex waves is generated.By adjusting the phase of the two feed networks,the two microstrip antenna arrays generate OAM mode vortex waves of l=+1 and l=-2.The array antenna has a wide bandwidth because of the coupling between the radiation array elements.The measured results show that both array antennas achieve the impedance bandwidths of 780 MHz and 610 MHz and the port-to-port isolation better than 32.5 dB.