基于双焦点设计的平面波束扫描透镜天线研究

Research of planar beam-scanning lens antenna based on bifocal design

摘要:

为了提升平面透镜天线的扫描性能，以实现波束扫描或多波束应用，首先研究设计了单焦点平面透镜天线，针对单焦点平面透镜天线在大角度扫描时增益降低太快的问题，引入了反射阵和传统介质透镜的双焦点设计方法。基于阵列天线合成理论，计算了双焦点透镜天线的辐射特性。采用多层金属孔阵列单元，建模了平面透镜天线模型，仿真对比了单焦点透镜和双焦点透镜天线的扫描辐射特性。结果表明，在扫描范围（0°-27°）内，双焦点透镜天线的最低增益相对于单焦点透镜天线有明显提升，而且大角度扫描方向图形状也有改善，证明了双焦点的设计方法有效提升了平面透镜的扫描性能。

Abstract:

In order to improve the scanning performance of planar lens antenna to realize the practical application in multi-beam, a single-focus lens antenna was designed firstly. For the problem that the gain of single-focus planar lens antenna decreases too fast during large-angle scanning, a bifocal design method in the reflective array and the conventional dielectric lens is innovatively introduced. Based on the theory of array antenna synthesis, the radiation characteristics of bifocal lens antenna are theoretically calculated. The planar lens antenna was modeled bye Metallic Hole Arrays unit, and the scanning radiation characteristics of the single-focus lens and the bifocal lens antenna were simulated and compared. The results show that the minimum gain of the bifocal lens antenna is significantly improved compared with the single-focus lens antenna in the scanning range(0°-27°), and the shape of the large angle scanning pattern is also improved. It is proved that the bifocal design method effectively improves the scanning performance of the planar lens.