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प्रश्न
The frequencies of two side bands in an AM wave are 640 kHz and 660 kHz respectively. Find the frequencies of carrier and modulating signal. What is the bandwidth required for amplitude modulation?
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उत्तर
Let frequency of carrier wave be fc and frequency of modulating wave be fm
fc+ fm = 660 kHz ....... (i)
fc− fm = 640 kHz ....... (ii)
Solving (i) and (ii), we get
2 fc = 1300
⇒ fc = 650 kHz
Now,
fc+ fm = 660 kHz
650+ fm = 660 kHz
⇒fm = 10 kHz
We know,
Bandwidth = 2×fm = 20 kHz
Hence,
Frequency of carrier signal is 650 kHz
Frequency of modulating signal is 10 kHz
Bandwidth required for amplitude modualtion is 20 kHz
संबंधित प्रश्न
Explain the process of amplitude modulation.
Explain any two factors which justify the need for modulating a low frequency base-band signal.
Solve the following question.
A message signal of frequency 20 kHz and peak voltage 10 V is used to modulate a carrier of frequency 2 MHz and peak voltage of 15 V. Calculate the modulation index. Why the modulation index is generally kept less than one?
In amplitude modulation ______.
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.
Compute the LC product of a tuned amplifier circuit required to generate a carrier wave of 1 MHz for amplitude modulation.
Why is a AM signal likely to be more noisy than a FM signal upon transmission through a channel?
An amplitude-modulated wave is represented by Cm(t) = 10(1 + 0.2 cos 12560t) × sin (111 × 104t) volts. The modulating frequency in kHz will be ______.
The maximum amplitude for an amplitude modulated wave is found to be 12V while the minimum amplitude is found to be 3V. The modulation index is 0.6x where x is ______.
A signal of 5 kHz frequency is amplitude modulated on a carrier wave of frequency 2 MHz. The frequencies of the resultant signal are ______.
