This paper presents a low-cost multi-layered electrically-small dielectric lens for improving the maximum radiation gain and side-lobe-level (SLL) for a directive antenna such as a horn antenna utilizing a new additive manufacturing filling technique. For obtaining the best performance of such a lens, the variation of the dielectric constant of outer layers toward the inner layers should be smooth and continuous while the transition should happen fast for smaller physical dimensions. Since it will be very difficult and expensive to fabricate such a lens, the multi-layer stepped configuration becomes more practical and desirable. Instead of using different materials for different layers, the same material is used but with different densities. Therefore, the total size, fabrication cost, and complexity are reduced significantly. The gain of an open waveguide at 10 GHz is increased by 15 dB while SLL is kept below −15 dB using the proposed spherical dielectric lens. In addition, 59.26% aperture efficiency with 20.5 dBi total gain is achieved.

本文提出了一种低成本的多层电小型介电透镜，可利用新型增材制造填充技术来改善定向天线（例如喇叭天线）的最大辐射增益和旁瓣电平（SLL）。为了获得这种透镜的最佳性能，外层朝着内层的介电常数的变化应该是平滑且连续的，而对于较小的物理尺寸，过渡应该快速发生。由于制造这样的透镜将是非常困难且昂贵的，因此多层阶梯结构变得更加实用和期望。代替对不同的层使用不同的材料，而是使用相同的材​​料但具有不同的密度。因此，总尺寸，制造成本和复杂性显着降低。使用建议的球形介电透镜，在10 GHz时开放式波导的增益增加15 dB，而SLL保持在-15 dB以下。另外，实现了59.26％的孔径效率和20.5 dBi的总增益。