Question

In: Physics

2. An AM radio station broadcasts a signal at a carrier frequency ωc, with an amplitude...

2. An AM radio station broadcasts a signal at a carrier frequency ωc, with an amplitude modulation frequency of ωm << ωc,

E(t) = E0[1 + A sin(ωmt)] sin(ωct)

Show that this is the sum of a wave at the carrier frequency, the lower sideband (ωL = ωc−ωm), and the upper (high) sideband (ωH = ωc + ωm). What total bandwidth is required if the radio station wants to broadcast music that contains modulation frequency components from 20 to 10,000 Hz?

Solutions

Expert Solution

If we have f1​, f2​ and f3​ base band frequency signals in amplitude modulation and f1​<f3​<f2​ then,

Band width of amplitude modulated signal is given by,

Band width of AM signal=2× highest of baseband frequencies

BW=2×f2​ ....... (here f2​ is the highest baseband frequency)If you have any doubt, you can ask in the comment box.


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