Describe with respect to antenna (i) radiation pattern (ii) directive gain (iii) power gam (iv) polarization

Describe with respect to antenna (i) radiation pattern (ii) directive gain (iii) power gam (iv) polarization
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Answer :

(i) Radiation pattern:-A graph or diagram which tells us about the manner in which an antenna radiates more power in different directions is known as the radiation patteren of antenna. 

(ii) Directive gain:- Directive gain is defined as the ratio of the power desity in a particular direction of one antenna to the power density that would be radiated byisotropic antenna in the same direction. 

(iii)Power gain:-The power gain of an antenna is defined as the ratio of power fed to an isotropic antenna to the power fed to a directional antenna, to develop the same field strength at the same direction.

(iv)Polarization:-Polarization is defined as the direction of the electric vector in the electromagnetic wave radiated by the transmitting antenna. 
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