Definitions and fundamentals of electromagnetic noise, interference, and compatibility

The terms electromagnetic noise, interference, and compatibility are defined, and some of the different definitions for these terms in current usage are discussed with emphasis on international definitions. For this paper, noise is defined as all electromagnetic energy except that associated with the desired signal for a specific system of interest. Interference is considered to be an undesirable effect of electromagnetic noise upon a system or subsystem rather than as a cause or source of noise. Electromagnetic compatibility is the condition that prevails when telecommunications equipment is collectively performing its individually assigned functions in a common electromagnetic environment without causing or suffering unacceptable interference. Selected aspects of the fundamentals of noise, interference, and compatibility are discussed.