Chapter 45 - EMC

Abstract

Electromagnetic interference (EMI) is a serious and increasing form of environmental pollution. Its effects range from minor annoyances due to crackles on broadcast reception to potentially fatal accidents due to corruption of safety-critical control systems. Various forms of EMI may cause electrical and electronic malfunctions, can prevent the proper use of the radiofrequency (rf) spectrum, can ignite flammable or other hazardous atmospheres, and may even have a direct effect on human tissue. As electronic systems penetrate more deeply into all aspects of society, both the potential for interference effects and the potential for serious EMI-induced incidents will increase. The threat of EMI is controlled by adopting the practices of electromagnetic compatibility (EMC). This is defined as, “The ability of a device, unit of equipment, or system to function satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to anything in that environment.” The term EMC has two complementary aspects: it describes the ability of electrical and electronic systems to operate without interfering with other systems, and it describes the ability of such systems to operate as intended within a specified electromagnetic environment.