An Evaluation Method for Radiated Emissions of Components and Modules in Mobile Devices

In this paper, a component-level electromagnetic interference (EMI) evaluation method for multifunctional mobile devices is suggested. The proposed method is based on the extraction of the transfer function between the component-level and the system-level radiated emissions. To demonstrate the practical correlation between the near-field emission from components or modules and far-field radiation from systems, measurement-based transfer functions are extracted by testing various mobile phones integrating camera modules as a target component. A specification for the component-level EMI evaluation is developed with a statistical transfer function and the system-level EMI regulation of CISPR. The proposed evaluation method is experimentally verified using 86 real mobile phones with a good correlation between the component-level and the system-level evaluation results.