Identify the mathematical expression for amplitude modulated wave: (a) Ac sin [{ωc + k1vm(t)}t + φ ] (b) Ac sin {ωc t + φ + k2 vm(t)} (c) {Ac + k2 vm(t)} sin (ωc t + φ ) (d) Ac vm(t) sin (ωc t + φ )
Correct option is C) In amplitude modulation, the amplitude (signal strength) of the carrier wave is varied in proportion to that of the message signal. In option "C" amplitude is varied according to message signal. The mathematical expression for amplitude modulated wave is- Ac+k2vm(t)sin[ωc(t)+ϕ]