A Resonant-Cavity Antenna with High-Gain and Wide Bandwidth with an All-Dielectric 3D-Printed Superstrate

The 3D-printing of dielectric superstrates of Resonant Cavity Antennas has advantages of fast prototyping and flexibility in the realization of customized layouts. In this work, the low dielectric permittivity of test filaments is experimentally measured for their use in superstrates of Resonant Cavity Antennas. A suitable combination of thickness, side extension and permittivity of the superstrate can enhance the antenna gain of the primary source over a broad frequency interval. With non-periodic and perforated layouts, instead, the radiative properties can be improved in terms of reductions of the Side-Lobe Level. The use of an all-dielectric superstrate in the design of an RCA is presented, demonstrating the possibility of obtaining a broadband gain enhancement with a single dielectric layer of low permittivity.