Broad band invisibility cloak made of normal dielectric multilayer

TL;DR

This paper demonstrates a broadband microwave invisibility cloak using multilayer dielectric slabs, achieving effective cloaking from 8 GHz to 18 GHz with simple design and fabrication.

Contribution

The work introduces a practical broadband cloaking device made of normal dielectric materials using a straightforward multilayer approach based on effective medium theory.

Findings

Achieved cloaking effect across 8-18 GHz frequency range.

Fabricated cloak using FR4 dielectric slabs with air gaps.

Validated performance through simulations and measurements.

Abstract

We present the design, fabrication and performance test of a quasi three-dimensional carpet cloak made of normal dielectric in the microwave regime. Taking advantage of a simple linear coordinate transformation we design a carpet cloak with homogeneous anisotropic medium and then practically realize the device with multilayer of alternating normal dielectric slabs based on the effective medium theory. As a proof-of-concept example, we fabricate the carpet cloak with multilayer of FR4 dielectric slabs with air spacing. The performance of the fabricated design is verified through full-wave numerical simulation and measurement of the far-field scattering electromagnetic waves in a microwave anechoic chamber. Experimental results have demonstrated pronounced cloaking effect in a very broad band from 8 GHz to 18 GHz (whole X and Ku band) due to the low loss, non-dispersive feature of the multilayer dielectric structure.