Electromagnetic Interference and Compatibility Quick Guide v1.0 Introduction: This is a quick, informal reference to the very basics of electromagnetic compatibility (EMC) caused by electromagnetic interference (EMI) and is a work in progress. It provides an introduction to the theory of EMI and also practical aspects of dealing with the radiofrequency (RF) aspects of equipment under test (EUT). v1.0 is mainly a compilation of the references. Email questions or comments to aloksubbarao@gmail.com Electromagnetic Interference and Compatibility Quick Guide v1.0 EMI Overview Electromagnetic Interference (EMI) caused by between systems, subsystems, or components in electronic devices can cause unwanted effects ranging from minor (e.g. phone RF causing speaker sound, RF interference with wi-fi causing weak signal) to catastrophic (aircraft radar failure). EM waves can be radiated through space or conducted via wires. Designers of electronic systems should minimize EMI from the outset rather than dealing with it once it has become a problem. Electromagnetic compatibility (EMC) has 5 key areas:  Radiated emission (RE)  Electrostatic discharge (ESD)  Susceptibility to RF fields  Power disturbances  Internal crosstalk Generally, radiated emission is the most difficult obstacle hindering ideal EMC. Radiated emission occurs when high