Q. An un modulated AM signal produces a current of 5.4 A. If the modulation is 100 percent,
calculate (a) the carrier power,
(b) the total power,
(c) the sideband power when it is transmitted through an antenna having an impedance of 50Ω.- Published on 12 Oct 15a. 1458 W, 2187.5 W, 729.25 W
b. 278 W, 2187.5 W, 1917.25 W
c. 1438 W, 2187.5 W, 759.25 W
d. 280 W, 2187.5 W, 750.25 W
ANSWER: 1458 W, 2187.5 W, 729.25 W
a) PC=I2R = (5.4)2*50 = 1458W
b) IT = Ic√(1+m2/2) = 5.4√(1+12/2)
=6.614 A
PT = IT2R
= (6.614)2 * 50
= 2187.25 W
c) PSB = PT - PC
= 2187.25 - 1458 W
= 729.25W (for two bands)
For single band, PSB = 729.25/2
= 364. 625 W
