近场与远场发射图示讲解|Near Field, Far Field Radiation

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	In dealing with a Radiation Source --be it an Antenna or a Circuit Board: - The dominant energy in the Far Field is Electric. -- Plane Wave radiation is how radio works 377 ohms is the impedance of free space - The dominant energy in the Near Field  is Magnetic. - -
In any high frequency signal the dominant radiation component under ~1/6 wavelength from the source, is Electromagnetic; this is referred to as Near Field radiation. Any signal beyond ~1/6 wavelength, is Electrostatic, and is referred to as Far Field radiation; sometimes called the Plane Wave. Plane Wave radiation is how radio works and that the 377 ohms is the impedance of free space.