基于圆微带天线阵的射频涡旋电磁波的产生

射频涡旋电磁波等相位面呈涡旋状，是一种携有新自由度-轨道角动量的电磁波。在轨道角动量模式理论分析的基础上，提出了在中心频率6 GHz处产生携有轨道角动量的涡旋电磁波的一种圆微带天线阵新结构，设计了以双层圆形微带天线为阵元组成的圆形阵列天线，通过控制馈源的相位差，得到模式量子数为0，1，2， 3， 4的轨道角动量。仿真结果表明:携轨道角动量的电磁波矢量电场图具有涡旋波阵面的特性，合适的阵列半径和馈线排列分布将产生携有良好轨道角动量特性的涡旋电磁波，而不当的阵列半径或馈线排列分布将出现能量的分散或者相互耦合的问题。

Radio vortex electromagnetic beam generation based on circular patch array antenna

The vortex electromagnetic wave has a new degree of freedom named orbital angular momentum (OAM), which arises from the vortex phase term. Recently it has received intensive attention in the application to the wireless communication field. In radio waves, the array antenna is an effective method to generate vortex electromagnetic waves carrying orbital angular momentum. We proposed a new design of patch array antenna carrying orbital angular momentum at 6 GHz. In this design, eight proximity-fed circular patches arranged on a circle with equidistant space. By controlling the phase delay, we got OAM modes of quantum number 0, 1, 2, 3, 4, and obtained the vortex electromagnetic wave carrying orbital angular momentum. In addition, the appropriate array radius and feed transport line were two keys to generate good properties of vortex waves carrying orbital angular momentum.