This paper presents the design and fabrication of an ultra-thin and flexible electromagnetic interference (EMI) shield that is capable of rejecting multiple unwanted frequencies. The design starts with the equivalent circuit model of periodic concentric rings to determine the initial geometrical dimensions of the rings efficiently. Then it followed by full-wave electromagnetic simulation to fine-tune the final dimensions for the desired frequency response. Impacts of various geometrical designs on the EMI shielding performance of the concentric ring design are analyzed and discussed. With these results, an ultra-thin and flexible EMI shield is fabricated using the screen printing technique. Finally, its multi-band rejection performance is validated experimentally. Good correlation between measurement and simulation is demonstrated in this paper.
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