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प्रश्न
In amplitude modulation, the modulation index m, is kept less than or equal to 1 because ______.
- m > 1, will result in interference between carrier frequency and message frequency, resulting into distortion.
- m > 1 will result in overlapping of both side bands resulting into loss of information.
- m > 1 will result in change in phase between carrier signal and message signal.
- m > 1 indicates amplitude of message signal greater than amplitude of carrier signal resulting into distortion.
पर्याय
a and b
b and d
c and a
d and b
उत्तर
b and d
Explanation:
Modulation index: The ratio of change of amplitude of carrier wave to the amplitude of original carrier wave Is called the modulation factor or degree of modulation or modulation index (ma).
The modulation index (m) of amplitude modulated wave is m = `("amplitude of message signal" (A_m))/("amplitude of carrier signal" (A-c))`
If m > 1, then Am > Ac
In this situation, there will be the distortion of the resulting signal of amplitude modulated wave.
The maximum modulation frequency `(m_f)` of AM wave is
`m_f = (Δv_(max))/(v_m(max)) = "Frequency deviation"/"Maximum frequency value of modulating wave"`
If `m_f > 1`, then `Δv_(max) > v_m`
It means, there will be overlapping of both sidebands of a modulated wave resulting in loss of information.
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संबंधित प्रश्न
For an amplitude modulated wave, the maximum amplitude is found to be 10 V while the minimum amplitude is found to be 2 V. Determine the modulation index μ. What would be the value of μ if the minimum amplitude is zero volt?
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Answer the following question.
If A and B represent the maximum and minimum amplitudes of an amplitude-modulated wave, write the expression for the modulation index in terms of A and B.
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Why is a AM signal likely to be more noisy than a FM signal upon transmission through a channel?
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- peak carrier voltage and
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Draw the plot of amplitude versus ‘ω’ for an amplitude modulated wave whose carrier wave (ωc) is carrying two modulating signals, ω1 and ω2 (ω2 > ω1).
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- 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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