LAUSR

Various types of electromagnetic shielding structures for specific frequency band have been reported in recent years. A gasket-free electromagnetic shielding structure using folded quarter-wavelength substrate integrated waveguide (FQ-SIW) resonators for 2.4-GHz band is one of them. In the structure, SIW resonators of different resonant frequencies in 2.4-GHz band are cascaded and positioned on inner walls of a gap. The structure is almost free of deterioration since contact-type gaskets are not used. In this paper, a gasket-free electromagnetic shielding structure for 2.4-GHz and 5-GHz bands using cascaded dual-behavior (DB) SIW resonators is proposed and evaluated. A DB-SIW resonator consists of two FQ-SIW resonators sharing one coupling slot and has two almost-independent resonant frequencies in the two bands. The design results showed attenuation characteristics at the two bands, and the configuration was miniaturized by 4% compared with conventional cascaded FQ-SIW resonators. Shielding effectiveness (SE) was also evaluated, and the measured results showed more than 20-dB improvement of SE near the two bands, though frequency shifts were observed.