This paper presents a bandpass frequency selective surface (FSS) radome based on fully metallic gap waveguide (GW) technology. The element of the proposed FSS radome consists of a conventional cross-dipole slot etched on metallic plates and positioned over a groove GW cavity. A design with a single GW cavity layer was initially produced which was later optimised for performance, to comprise a dual GW cavity layer, while considering both functionality and manufacturability. It is shown that the proposed FSS element offers a stable and wide bandpass (from 26-30 GHz) performance in the broadside direction for both transverse electric (TE) and transverse magnetic (TM) polarizations. For oblique angle of incidence, the suggested FSS element works up to 30 • with a reduction in usable bandpass bandwidth performance to 26-28 GHz for both TE and TM polarizations. A 20 × 20-element GW-FSS array prototype has been fabricated and measured, which was integrated with a fixed beam array antenna to further validate its functionality as a filtering radome. The findings show an excellent agreement between simulations and measurements. Hence, the proposed GW-FSS represents a great opportunity to develop a all-metallic FSS with low insertion loss, sharp-roll-off filtering, wideband performance and inexpensive fabrication cost.
This paper presents a bandpass frequency selective surface (FSS) radome based on an all-metallic gap-waveguide (GW) operating at broadside (θ = 0 • ) for the mmWave band. The proposed GW-based FSS uses conventional cross-dipole slots and a dual-GW cavity over three distinct metallic layers. The top and bottom layers consist of cross-dipole slots, whereas the middle layer consists of a dual GW-cavity and cross-dipole slots layer. The proposed GW-based FSS provides a stable broad bandpass, from 26 − 30 GHz, in the broadside direction for both transverse electric (TE) and transverse magnetic (TM) polarisations. A prototype of the designed 20×20 GW-based FSS finite array was manufactured and measured with an insertion loss of 0.6 dB. A good agreement between simulations and measurements is shown in broadside directions. The proposed GW-based FSS offers an excellent low-insertion-loss and cost-effective solution to fully metallic bandpass FSS radomes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.