Numerical shielding evaluation of clip-type shield can in mobile phones

On-board shield cover commonly named shield can in portable wireless devices, is often used to reduce the emission from noisy components to the outside the products and to protect sensitive devices against external fields. Shielding performance of the shield cans at high frequencies over GHz is dominated by coupling through the seams between the can and its fixture or the can and printed circuit board (PCB) ground. In modern mobile phones, a clip-type shield can is popularly used due to providing low cost and design flexibility. In this paper, the effect of clip types on the shielding performance of a shield can is investigated by means of 3-D full-wave simulation using commercial software. From the analysis results, some guidelines for shield design in mobile devices are suggested.