Design and development of angularly stable and polarisation rotating FSS radome based on substrate-integrated waveguide technology

摘要

In this paper, the design of a novel polarisation rotating frequency selective surface (FSS) radome is presented based on substrate integrated waveguide (SIW) technology. The proposed radome consists of an FSS core with Y-shaped slots on either side of the substrate and surrounded by metallic vias. The primary function of the core is to select the linear polarisation from the impinging electromagnetic (EM) wave and to rotate the wave into 90 degrees clockwise direction in the X-band regime. The radome structure shows a relative bandwidth of 13.2% from 9.2 GHz to 10.5 GHz with impedance matching better than -10 dB and the insertion loss (IL) better than 0.5 dB. The proposed structure shows very stable resonance performance with sharp band edge characteristics compared to the existing FSS radomes. Also, the conformal analysis of the proposed structure has been carried out to study its behaviour for real-time radome applications. Finally, to prove the efficacy of the proposed structure, a prototype has fabricated and measured its performance in a free space measurement setup. A good agreement is observed between the experimental and simulated results. Furthermore, the conversion of E-field pattern to H-field pattern and vice-versa is proved from the experimental verification.