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Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

harmonic analysis
the branch of mathematics dealing with the decomposition of signal functions as a linear combination of basis functions which represent "waves" of various frequencies.

When the basis functions are sines and cosines each with a frequency that is an integer multiple of the signal's frequency, we have trigonometric harmonic analysis, in other words classical Fourier analysis, which provides the amplitudes and phases of the constituent sinusoids.