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A 3D scalar electromagnetic imaging of dielectric objects buried under a rough surface is presented. The problem has been treated as a 3D scalar problem for computational simplicity as a first step to the 3D vector problem. The complexity of the background in which the object is buried is simplified by obtaining Green's function of its background, which consists of two homogeneous half-spaces, and a rough interface between them, by using Buried Object Approach (BOA). Green's function of the two-part space with planar interface is obtained to be used in the process. Reconstruction of the location, shape, and constitutive parameters of the objects is achieved by Contrast Source Inversion (CSI) method with conjugate gradient. The scattered field data that is used in the inverse problem is obtained via both Method of Moments (MoM) and Comsol Multiphysics pressure acoustics model.

Placing dielectric lens structures into an antenna's aperture has proven to be one of the most reliable methods of enhancing its gain. However, the selected material and the prototyping method usually limit their fabrication process. With the advances in 3D printing technology and their applications, the microwave designs that were either impractical or impossible in the past to manufacture using traditional methods, are now feasible. Herein, a novel prototyping method by using 3D-printer technology for low-cost, broadband, and high gain dielectric lens designs has been presented. Firstly, the elliptical lens design has been modeled in the 3D EM simulation environment. Then fused deposition modeling based 3D-printing method has been used for the fabrication of the dielectric lens. The measured results of the 3D printed antenna show that the lens antenna has a realized gain of 17 to 20.5 dBi over 8-12 GHz. Moreover, the comparison of the prototyped antenna with its counterpart dielectric lens antenna in the literature has indicated that the proposed method is more efficient, more beneficial, and has a lower cost.

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