Electromagnetics interference (EMI) radiation from airflow openings in personal computers shielded enclosures: An experimental study

摘要

In this paper, electromagnetic radiation leakage through airflow openings found in modern personal computers and mobile electronic devices (i.e., enclosures) is experimentally studied in the low frequency regime. Three different designs of enclosure's covers are assessed through experimental work. The three airflow covers of the shielding enclosure cases comprise the use of all holes (case 1), hexagon (case 2), slotted cover (case 3), and a reference case of a solid cover with no openings. Comparison is then made between the designed covers in reference to the solid cover that mimics a closed enclosure. The measurements are conducted based on capturing the amount of power transfer, through the transmission coefficient S21 , in both near vicinity and far-region from the enclosure's opening. It was found that hexagonal airflow cover provides better shielding effectiveness than cases 1 and 3, especially in the near-vicinity region to the enclosure.