Draw a block diagram of a simple amplitude modulation. Explain briefly how amplitude modulation is achieved.

Explanation

Production of Amplitude Modulated wave : A conceptually simple method to produce AM wave is shown in the following block diagram.

Here, the modulating signal `A_(m) sin w_(m) `t is added to the carrier signal `A_(c) sin w_(c)t` to produce the signal x(t). This signal`x(t)=A_(m) sin w_(m) t+A_(c) sin w_(c) t` is passed through a square law device law device which produces an output.
`y(t)=Bx(t)+C x^(2)(t)`
Where, B and C are constants.
This signal is passed through a band pass filter which rejects dc. The output of the band pass filter is therefore, an `A_(m) ` wave.