Question:
(i) Draw the plot of amplitude versus ‘ω’ for an amplitude modulated wave whose carrier wave (ωc ) is carrying two modulating signals, ω1 and ω2 (ω2 > ω1).
[Hint: Follow derivation from Eq 15.6 of NCERT Textbook of XII]
(ii) Is the plot symmetrical about ωc? Comment especially about plot in region ω < ωc
(iii) Extrapolate and predict the problems one can expect if more waves are to be modulated
(iv) Suggest solutions to the above problem. In the process can one understand another advantage of modulation in terms of bandwidth?
Solution:
(ii) The plot is not symmetrical
(iii) There are chances of mixing of signals
(iv) By increasing the bandwidth and frequency of the carrier waves, more signals can be accommodated.