Advertisements
Advertisements
Question
Given modulation index physical significance .For an amplitude modulated wave, the maximum amplitude is found to be 10 V while the minimum amplitude is 2 V. Determine the modulation index μ ?
Solution
Physical significance of modulation Index.
To determine the strength and quality of transmitted signal. If the modulation index is small, the amount of variation in the carrier amplitude is small. Thus, the audio signal transmitted will not be strong. The greater the degree of modulation, the stronger and clearer will be the audio signal during reception.
Maximum amplitude, Amax = 10 V
Minimum amplitude, Amin = 3 V
Thus modulating index `mu =(A_(max) -A_(min))/(A_(max) +A_(min)) = (10+3)/(10 -3) = 13/7 = 1.85`
RELATED QUESTIONS
The process of superimposing a low frequency signal on a high frequency wave is_______ .
Define modulation index.
Draw a sketch of a sinusoidal carrier wave along with a modulating signal and show how these are superimposed to obtain the resultant amplitude modulated wave
How are side bands produced?
A carrier wave of peak voltage 15 V is used to transmit a message signal. Find the peak voltage of the modulating signal in order to have a modulation index of 60%
In a communication system, what is meant by modulation?
State any two types of modulation
In the block diagram of a simple modulator for obtaining an AM signal, shown in the figure, identify the boxes A and B. Write their function.
Broadcasting antennas are generally ______.
A speech signal of 3 kHz is used to modulate a carrier signal of frequency 1 MHz, using amplitude modulation. The frequencies of the sidebands will be ______.