Benefits of Using a High-permittivity and Low-loss Printable Material for Sub-wavelength Deflectors

In this paper, sub-wavelength structured deflectors operating in Ka-band are designed and tested to demonstrate the advantages of using a new printable high-permittivity and low-loss composite material for antenna applications. This material is composed of COC (Cyclic Olefin Copolymer) polymer loaded with titanium oxide particles at 36%vol. and is compatible with the single-step 3D-printing FDM (Fused Deposition Modelling) process. This thermoplastic composite (COC-TiO
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) features a high permittivity of 7.7 and a low dielectric loss with loss tangent of 1.10
⁻³
over a wide frequency range from 10 to 40 GHz. Moreover, it offers a good resistance against temperature with a Heat Deflection Temperature of 110°C. To demonstrate the benefits of such a material, a sub-wavelength deflector is fabricated in COC-TiO
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composite and compared to its counterpart printed in ABS (Acrylonitrile Butadiene Styrene). Simulation and measurement results show numerous advantages when using the high-permittivity material, mainly in reducing the component’s thickness and weight, enhancing the efficiency and reducing the side lobes levels.