λ = c/f
= 3*10^8/(3*10^9)
=10 cm
The gain Ap = 6D^2/ λ ^2
& Ap = 10log Ap
26 = 10log Ap
Ap = 398.11
Thus
398.11 = 6*D^2/10^2
D = 81.45 cm
and half power point beam width
Φ = 58 λ /D
=58*10/81.45
Φ = 7.12o
(Q). A parabolic antenna operating at 3GHz has a gain of 26dB. Calculate the diameter of the antenna and half power point beamwidth.
by 