SOLVED Numerical's - Antenna Theory - Page 7.


19) At the far field, an antenna produces





Calculate the directive gain and the directivity of the antenna?

SOLUTION:





















20) For a thin dipole λ/16 long, find the
a) Directive gain
b) Directivity
c) Effective area
d) Radiation resistance

SOLUTION:


a)

























On substituting we get,

Gφ = 1.5 sin2θ

b) Directivity, D = Gφ, max = 1.5

c) Effective Area, Ae = (λ2 / 4π) Gφ = (1.5 λ2 sin2θ) / 4π

d) Radiation Resistance Rrad




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