EFIE

The electric-field integral equation is a relationship that allows the calculation of an electric field (E) generated by an electric current distribution (J).

When all quantities in the frequency domain are considered, a time-dependency ${\displaystyle e^{+jwt}\,}$ that is suppressed throughout is assumed.

Beginning with the Maxwell equations relating the electric and magnetic field an assuming linear, media with permeability ${\displaystyle \epsilon \,}$ and permittivity ${\displaystyle \mu \,}$:

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