Single-layer miniaturized loaded frequency selective surfaces with enhanced bandwidth

In this paper, a novel single-layer miniaturized loaded frequency selective surface (FSS) with enhanced bandwidth operating over the GPS and DCS 1800 frequency band is presented, in which each periodic cell consists of double square loops with different capacitive loadings. To eliminate the undesired coupling between unit cells, the unit cells are placed in the substrate integrated waveguide (SIW) cavity structure. A S-band FSS with such structures is designed, the simulated results show that a band-pass bandwidth of 24.5% (1.49 GHz to 1.88 GHz) is obtained with an insertion loss of less than 3 dB for scan angles up to 45 degree in both TE and TM polarization while the bandwidth of normal loaded FSS is about 3%-5%. Furthermore the FSS dimension is miniaturized to 0.08 lambda (lambda refer to the resonant wavelength).