Region of space between a transmitting and receiving antenna
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Several examples of how Fresnel zones can be disrupted
A Fresnel zone (English: /freɪˈnɛl/fray-NEL), named after physicist Augustin-Jean Fresnel, is one of a series of confocal prolate ellipsoidal regions of space between and around a transmitter and a receiver. The primary wave will travel in a relative straight line from the transmitter to the receiver. Aberrant transmitted radio, sound, or light waves which are transmitted at the same time can follow slightly different paths before reaching a receiver, especially if there are obstructions or deflecting objects between the two. The two waves can arrive at the receiver at slightly different times and the aberrant wave may arrive out of phase with the primary wave due to the different path lengths. Depending on the magnitude of the phase difference between the two waves, the waves can interfere constructively or destructively. The size of the calculated Fresnel zone at any particular distance from the transmitter and receiver can help to predict whether obstructions or discontinuities along the path will cause significant interference.
A Fresnelzone (English: /freɪˈnɛl/ fray-NEL), named after physicist Augustin-Jean Fresnel, is one of a series of confocal prolate ellipsoidal regions...
analysis by French physicist Augustin-Jean Fresnel, they are sometimes called Fresnelzone plates in his honor. The zone plate's focusing ability is an extension...
or its shape. There are several types of Fresnelzone antennas, namely, Fresnelzone plate, offset Fresnelzone plate antennas, phase correcting reflective...
In optics, the Fresnel diffraction equation for near-field diffraction is an approximation of the Kirchhoff–Fresnel diffraction that can be applied to...
The Fresnel integrals S(x) and C(x) are two transcendental functions named after Augustin-Jean Fresnel that are used in optics and are closely related...
by using the phenomenon of diffraction. Such patterned sheets, called Fresnelzone plates, have long been used for focusing laser beams, but have so far...
spot, Poisson spot, or Fresnel spot is a bright point that appears at the center of a circular object's shadow due to Fresnel diffraction. This spot played...
A Fresnel lens (/ˈfreɪnɛl, -nəl/ FRAY-nel, -nəl; /ˈfrɛnɛl, -əl/ FREN-el, -əl; or /freɪˈnɛl/ fray-NEL) is a type of composite compact lens which reduces...
based on Fresnel number. Fraunhofer distance Fresnel diffraction Fresnel imager Fresnel integral Fresnelzone Near and far field Talbot effect Zone plate...
from a reflection is determined by the location of the object in the Fresnelzone of the antennas. Home or consumer grade two-way satellite Internet service...
lens for Fresnelzone plates. Graphene lenses effectively concentrate light of ʎ = 850 nm onto a single point 120 μm away from the Fresnelzone plate (Figure...
different Fresnelzones, the signal path formed by the reflection of the human body changes, and if people move vertically through Fresnelzones, the change...
systems using the slow atomic beams can use the Fresnelzone plate (Fresnel diffraction lens) of a Fresnel diffraction mirror as focusing element. The imaging...
avoid attenuation of the beam, an area around the beam called the first Fresnelzone must be free from obstacles. Obstacles in the signal field cause unwanted...
to partial obstruction by a physical object present in the innermost Fresnelzone. Obstacles that commonly cause NLOS propagation include buildings, trees...
pinhole. The pinhole, in this case, is equivalent to a Fresnelzone plate with a single zone. The value s2/λ is in a sense the natural focal length of...
transducer (near zone length or Fresnelzone), the beam width narrows to half of the transducer width, and after that the width increases (far zone length or...
between the radios and antennas may introduce significant additional loss. Fresnelzone losses due to a partially obstructed line of sight path. Doppler shift...
enough for useful reception, usually rights of way cleared to the first Fresnelzone are required. Therefore, on the surface of the Earth, microwave communication...
for useful reception, unobstructed rights of way cleared to the first Fresnelzone are usually required. Wavelengths are small enough at microwave frequencies...
pinholes that are arranged in a pattern which is similar to the rings in a Fresnelzone plate, but with the ability to bring light to much sharper focus. The...
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