In this paper, an innovative, novel method to eliminate the internal reflections at the lens/air boundary of the radar sensors with dielectric lenses made of dense materials is proposed. Instead of traditional broadband matching technique, which requires the tooling of three additional layers with different materials on the lens surface, an alternative matching technique compatible with fabrication with today’s popular 3D printing technology is proposed. The proposed cylindrical perforated matching layer also consists of three layers whose electrical permittivity is equivalent to its conventional three-layer matching layer case. This is achieved by arranging the material density for each layer. Consequently, a simple, low-cost matching layer that is constructed by using the material of the lens is proposed for broadband lenses with dense materials. Its fabrication is simple and compatible with additive manufacturing technique. A hemispherical lens prototype consisting of circular corrugated matching layer is manufactured. The lenses are also simulated with a widely used full-wave EM analysis tool. Simulation results of the fabricated broadband lenses are confirmed successfully by the experimental results in 18–24 GHz frequency band.

中文翻译：

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用于宽带介电透镜的具有穿孔、非均匀层的阻抗匹配技术

在本文中，提出了一种采用致密材料制成的介电透镜来消除雷达传感器透镜/空气边界处内反射的创新方法。与传统的宽带匹配技术不同，后者需要在镜片表面加工三个具有不同材料的附加层，而是提出了一种与当今流行的 3D 打印技术兼容的替代匹配技术。所提出的圆柱形穿孔匹配层也由三层组成，其介电常数与其传统的三层匹配层情况相当。这是通过为每一层安排材料密度来实现的。因此，提出了一种使用透镜材料构建的简单、低成本的匹配层，用于具有致密材料的宽带透镜。其制造简单且与增材制造技术兼容。制造了由圆形波纹匹配层组成的半球形透镜原型。镜头还使用广泛使用的全波 EM 分析工具进行模拟。18-24 GHz频段的实验结果成功证实了制造的宽带透镜的模拟结果。