A term from radio communcations.
One of a (theoretically infinite) number of a concentric ellipsoids of revolution which define volumes in the radiation pattern of a (usually) circular aperture.
- The cross section of the first FresnelZone is circular. Subsequent FresnelZones are annular in cross section, and concentric with the first.
- Odd-numbered FresnelZones have relatively intense field strengths, whereas even numbered FresnelZones are nulls.
- FresnelZones result from diffraction by the circular aperture. (188)
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