EMI Reduction Techniques for Mobile Communication Devices

This paper describes the types of EMI and its reduction techniques for mobile communication devices. Initially electromagneticinterference (EMI) is generated due to parasitic effect of passive elements in switching devices; it generates commonmode (CM) and differentialmode (CM) types of noise. Both are known as conducted EMI. Second type of EMI is radiated. Radiated EMI can be generated outside the device or inside the device and it doesn't need a wire for transmitting. Both types of EMI harm the device abruptly and malfunction occurs. The maximum limit of EMI is decided by the FCC standards. So we have to reduce the EMI noise in such a manner that it follows the FCC standards. Radiated EMI can be reduced by using a proper shielding method and conducted EMI can be reduced by designing the EMI filter for both CM and DM noise. Thus, here we describe various types of EMI occurrence in mobile electronic devices and its basic solution to overcome these problems. Here this paper will show the shielding techniques and EMI filter to reduce both radiated and conductednoise.