Miniaturized Conformal Frequency Selective Surface for X-Band Electromagnetic Shielding

This paper proposes a miniaturized conformal band stop frequency selective surface for electromagnetic shielding in the X band from 8 to 12 GHz. The structure is realized on a flexible polyimide substrate, which allows seamless integration on curved platforms. The unit cell occupies an area of 5 mm × 5 mm and incorporates a meandered square loop combined with an inverted I dipole to achieve an electrical length of nearly 0.13 λ0 at the 10 GHz resonance. The surface provides a peak attenuation of 47 dB at 10 GHz with a fractional bandwidth of 40 percent, which fully covers the X band. The symmetric topology yields stable characteristics in both TE and TM modes and retains performance up to an incident angle of 80◦. The key novelty lies in the combination of miniaturization and conformal wideband shielding achieved through the hybrid resonant geometry, which enables compact scalable and angle stable operation. These features make the proposed surface suitable for high performance X band shielding in platforms that require both reduced size and robust frequency response.