Name: Propagation of Radio Waves: Sky Waves
Uploaded: 2019-07-19
Duration: 7 min 33 s
Description: Radio waves are known for their use in communication technologies such as television, mobile phones, and radios. Let’s discuss how radio waves propagate.

Question

Draw the plot of amplitude versus ‘ω’ for an amplitude modulated wave whose carrier wave

(ω_{c})

extrapolate and predict the problems one can expect if more waves are to be modulated.

Accepted Answer

The plot of amplitude versus ω can be shown in figure below.

To produce amplitude modulated wave the signal $x (t)$ is passed through a square law device

$∵ ω_{m_{2}} > ω_{m_{1}}$

So increasing order of frequencies is $(ω_{m_{2}} - ω_{m_{1}}), ω_{m_{2}}, ω_{m_{2}} (ω_{m_{2}} + ω_{m_{2}}) (ω_{c_{1}} - ω_{m_{2}}), (ω_{c} - ω_{m_{2}}), ω_{c}, (ω_{c} + ω_{m_{1}}) and (ω_{c} + ω_{m_{2}})$

Increasing order of amplitude $(ω_{m_{2}} - ω_{m_{1}}), ω_{m_{2}}, ω_{m_{2}} (ω_{m_{2}} + ω_{m_{2}}), ω_{c}, (ω_{c} + ω_{m_{1}}), (ω_{c} - ω_{m_{2}}), (ω_{c} - ω_{m_{1}}) and (ω_{c} - ω_{m_{2}})$

If more waves are to be modulated then there will be more crowding in the modulating signal in the region $ω < ω_{c}$ . That will result more chances of mixing of signals.

Draw the plot of amplitude versus ‘ω’ for an amplitude modulated wave whose carrier wave $(ω_{c})$ extrapolate and predict the problems one can expect if more waves are to be modulated.

Important Questions on Communication Systems

Learn and Prepare for any exam you want !

Draw the plot of amplitude versus ‘ω’ for an amplitude modulated wave whose carrier wave (ωc) extrapolate and predict the problems one can expect if more waves are to be modulated.

Important Questions on Communication Systems

Learn and Prepare for any exam you want !

Draw the plot of amplitude versus ‘ω’ for an amplitude modulated wave whose carrier wave $(ω_{c})$ extrapolate and predict the problems one can expect if more waves are to be modulated.