Define the following terms: (i) Polarization (ii) Antenna gain (iii)Antenna resistance (iv)Directivity

Define the following terms: (i) Polarization (ii) Antenna gain (iii)Antenna resistance (iv)Directivity
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1 Answer

Answer :

i) Polarization:-

It is defined as the direction of electric field vector in the EM wave radiated by the transmitting antenna.

ii) Antenna Gain:-

Antenna gain is defined as the ratio of the power density radiated in a particular direction to the power density radiated to the same point by the reference antenna.

It is mathematically given by,

image

Where

P = power density at some point with the given antenna

Pref = power density at same point with the reference antenna

iii)Antenna Resistance:- Radiation resistance is the AC antenna resistance and is equal to the ratio of the power radiated by the antenna to the square of the current at its feed point. It is

given by,

image
Iv) Directivity :-
It is the maximum directive gain which is obtained in only one direction in which the radiation is maximum.
That is directivity = Max. directive gain
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