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Electromagnetics

In physics, electromagnetics is the study of how waves and material behave at different frequencies. With pc boards, the terms that apply to electromagnetics are EMC (ElectroMagnetic Compatibility) and EMI (ElectroMagnetic Interference.) Even if your design doesn't have to meet certain requirements, it still has to operate in the intended environment. Problems caused by EMI are discussed in terms of “aggressor” or “victim.” An aggressor radiates energy or creates stray reactive fields. The victim malfunctions due to interference or ambient fields.
Besides the victim/aggressor problems, there is also problems caused by noise. Components, signal traces, and planes combine to form noise sources and antennas. These noise sources must have an amplification mechanism to propagate an electromagnetic field out into space. To reduce radiation levels, simply identify each component as either part of the noise source or part of the antenna. Almost everything in the system is part of the antenna. The antenna is a complex mechanism created by IC lead frames, circuit board signal and power traces, and cables. All IC’s potentially generate noise and, therefore radiate to some degree.
There are generally two actions to take: 1) spoil the antenna, and 2) suppress the noise at the source. Improved circuit board layout and more effective bypassing can improve EMI performance.

Electronics Reference and Tutorials

eEngineer - Electrical Engineering Topics

Magazine

Magazine

Clemson Vehicular Electronics Laboratory: Electromagnetic Compatibility

Downloads of design aid programs and spreadsheet calculators for the RF Designer

The RF Calculator program is a free utility program that calculates various radio frequency data