宽频大角度新型龙勃透镜设计与快速制造

Design and Rapid Fabrication of Broadband Wide-angle Flattened Luneburg Lens

传统龙勃透镜是一种具有梯度介电常数的球状介质天线，其功能是实现电磁波的球面会聚与定向发射，可广泛用于移动卫星通信。然而由于梯度介电常数分布、球面汇聚等特征，使得其制造尤为困难，且不易于集成。根据一种新型底面扁平龙勃透镜天线的设计方案，提出采用混合液体介质与3D打印技术相结合的制造方法，采用3D打印技术实现二维、三维透镜框架的快速制造，制备出介电常数大范围可调的混合液体介质（2．2～40．0）填充于框架中，所制备液固耦合的龙勃透镜天线在12．4～18．0GHz范围内具有宽频特性，并能实现全场扫描（-90°～90°）。所提出的方法为梯度介电常数透镜天线创新设计提供了一个新的实现手段，并将会进一步推动高性能透镜天线的实际应用。

Luneburg lens is a spherical dielectric lens with gradient refractive index. It can concentrate the collimated incident electromagnetic wave on its spherical surface, inversely, it can turn the point wave into plane wave and control the deflection angle of the exit wave. Due to the gradient index and spherically focusing features, the conventional luneburg lens is very difficult to be fabricated and integrated. A novel flattened Luneburg lens with a scanning range of [-90°, 90°] has been realized. Moreover, the lens has a broadband property from 12.4 GHz to 18 GHz. The gradient refractive index structure of the lens was realized by combining a liquid medium approach and the 3D printing technology, which resolved the fabricating problem of the complex structure of the lens. The flexibility of the liquids for a practical implementation endowed this innovative method a wide using perspective to the realization of other microwave devices with high performance.