COMPUTER NETWORKS AND COMMUNICATIONS
WIRELESS COMMUNICATION TECHNOLOGIES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Franklin distance
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Frii’s distance
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Fraunhofer distance
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Fergussion distance
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Detailed explanation-1: -Antenna near field distance equation As we know that space around an antenna is subdivided into four regions viz. reactive near field ( up to ), reactive radiating near field ( up to 3*), radiating (fresnel) near field (up to 2*D2 /) and radiating far field ( >=2*D2 /).
Detailed explanation-2: -Far field. The field, which is far from the antenna, is called as far-field. It is also called as radiation field, as the radiation effect is high in this area. Many of the antenna parameters along with the antenna directivity and the radiation pattern of the antenna are considered in this region only.
Detailed explanation-3: -The region where the transition of the electromagnetic field from reactive to radiative begins is called the radiative near-field region or the Fresnel region. The region furthest from the antenna is dominated by radiated electromagnetic fields and is called the far-field region or the Fraunhofer region.
Detailed explanation-4: -Far-Field (Fraunhofer region)-the region farthest away from the antenna where the field distribution is essentially independent of the distance from the antenna (propagating waves).