Near-field region

Near-field characteristics

The near field itself is further divided into the reactive near field and the radiative near field. The reactive and radiative near-field designations are also a function of wavelength (or distance). However, these boundary regions are a fraction of one wavelength within the near field. The outer boundary of the reactive near-field region is commonly considered to be a distance of ${\textstyle {\frac {1}{2\pi }}}$ times the wavelength (i.e., ${\textstyle {\frac {\lambda }{2\pi }}}$ or approximately 0.159λ) from the antenna surface. The reactive near-field is also called the inductive near-field. The radiative near field (also called the Fresnel region) covers the remainder of the near-field region, from ${\textstyle {\frac {\lambda }{2\pi }}}$ out to the Fraunhofer distance.