Post-fabricated EBG tape on electronic devices for RFI mitigation in WLAN bands

A thin tape with double-stacked electromagnetic bandgap (EBG) structure is proposed for RFI suppression in this paper. This thin EBG tape sticks on only single side of parallel-plate structure formed by printed-circuit board (PCB) and chassis, which is named as single-sided EBG tape (SS-EBG tape). SS-EBG tape provides a RFI solution in a post-fabricating way and can be fabricated with PCB process. Test boards are fabricated with different kinds of excitation and adopted to validate design concepts. By using double-stacked structure, SS-EBG tape has two bandgaps from 2.18 GHz to 2.51 GHz and from 4.8 GHz to 5.63 GHz. In Wi-Fi bands application, SS-EBG tape can provide additional 10 dB suppression level.