Ec 308 Awp Ch-10 Lens Antenna 3b455t

V. T. Patel Dept. of EC Engineering

EC 308 Antenna & Wave Propagation

Lecture-10 Lens Antenna

By-Manthan S. Manavadaria

V. T. Patel Dept. of EC Engineering

Chapter 10: Lens Antenna (Content)  Chapter 10: Lens Antenna

10.1

Dielectric lens, reflector lens antennas, Polyroid

“A microwave

antenna

in

which a dielectric lens is placed in front of the dipole or horn radiator to concentrate the radiated energy into a narrow beam or to focus received energy on the receiving dipole or

horn.”

Reference: http://www.radiogigabit.com/smart-lens-antennas/ Lens Antenna

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V. T. Patel Dept. of EC Engineering

Dielectric Lens  There are two types of lens antenna  Delay lances (electrical path length increased by lens medium) Ex. Dielectric lances, H plane metal-plate lenses  Fast lances (electrical path length decreased by lens medium) Ex. E plane metal-plate lenses

Lens Antenna

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V. T. Patel Dept. of EC Engineering

Dielectric Lens  There are two types of dielectric lenses  Non Metallic  Metallic/artificial  Non Metallic Dielectric lens

 This types is similar to optical lens  It may designed by ray analysis geometrical optics.

methods

of

 Metallic or Artificial Dielectric lens  This types is less heavy compare to nonmetallic lens  It consist of discrete metal particles of macroscopic size.

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V. T. Patel Dept. of EC Engineering

Non Metallic Dielectric lens (Fermat’s Principle)

Lens Antenna

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V. T. Patel Dept. of EC Engineering

Non Metallic Dielectric lens (Fermat’s Principle)

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V. T. Patel Dept. of EC Engineering

Non Metallic Dielectric lens

Reflection Coefficient

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V. T. Patel Dept. of EC Engineering

Metallic/Artificial Dielectric lens

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V. T. Patel Dept. of EC Engineering

Reflector Lens Antenna

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V. T. Patel Dept. of EC Engineering

Polyrod  A dielectric rod or wire can act as a guide for EM waves. This tendency to radiate is turned to advantage in the polyrod antenna. (made of Polystyrene)

Lens Antenna

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V. T. Patel Dept. of EC Engineering

Lens Antenna

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