Advertisements
Advertisements
Question
What is meant by term ‘modulation’? Draw a block diagram of a simple modulator for obtaining an AM signal.
Solution
The process of superimposing information contained in a low frequency signal on a high frequency signal is called modulation.
APPEARS IN
RELATED QUESTIONS
Explain any two factors which justify the need for modulating a low frequency base-band signal.
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.
Define amplitude modulation in a communication system.
In amplitude modulation ______.
The maximum amplitude of an A.M. wave is found to be 15 V while its minimum amplitude is found to be 3 V. What is the modulation index?
Why is a AM signal likely to be more noisy than a FM signal upon transmission through a channel?
On radiating (sending out) an AM modulated signal, the total radiated power is due to energy carried by ωc, ωc – ωm and ωc + ωm. Suggest ways to minimise cost of radiation without compromising on information.
An amplitude modulated wave is as shown in figure. Calculate
- the percentage modulation
- peak carrier voltage and
- peak value of information voltage.
The maximum and minimum voltage of an amplitude modulated signal are 60 V and 20 V respectively. The percentage modulation index 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 ______.
