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प्रश्न
Why is a AM signal likely to be more noisy than a FM signal upon transmission through a channel?
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उत्तर
In AM, the carrier wave's instantaneous voltage is varied by modulating wave voltage. On transmission, noise signals can also be added and the receiver assumes noise is a part of the modulating signal.
However, in FM, the carrier frequency is changed as per modulating wave's instantaneous voltage. This can only be done at the mixing/ modulating stage and not while the signal is transmitting in a channel. Hence, noise doesn’t effect the FM signal.
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संबंधित प्रश्न
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- Is the plot symmetrical about ωc? Comment especially about plot in region ω < ωc.
- Extrapolate and predict the problems one can expect if more waves are to be modulated.
- Suggest solutions to the above problem. In the process can one understand another advantage of modulation in terms of bandwidth?
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