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Modulation Index is the ratio of the maximum deviation frequency to the frequency of modulation. In other words it is the ratio of the spread in frequency spectrum to the frequency that was used to modulate the carrier.
For FM,
modulation index is given by the formula
mf= df/f
where,
mf=modulation index for FM
df=difference in carrier frequency
f=frequency of the signal
Wiki User
∙ 13y ago
Wiki User
∙ 12y agoNo modulation index for digital modulation .
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When modulation frequency is doubled the modulation index is halved and the modulating voltage remains constant the modulation system is?
the modulation system is of FM
What is the deviation ratio for frequency modulation?
Deviation ratio: In a frequency modulation system, the ratio of the maximum frequency deviation of the carrier to the maximum modulating frequency of the system under specified conditions
In which Analog to analog modulation methods does the peak amplitude?
Frequency modulation Phase modulation
Sinusoidal pwm generation using modulation index?
Not sure what type of modulation you are looking for, but there are two that can be manipulated, either individually or in conjunction:Frequency modulation index refers to the relation between the sine wave frequency (sine_freq) and the triangle (or saw-tooth) wave frequency (triang_freq).The frequency modulation index is equal to ((triang_freq)/(sine_freq)).Amplitude modulation index refers to the relation between the sine wave amplitude (sine_amp) and the triangle (or saw-tooth) wave amplitude (triang_amp).The amplitude modulation index is equal to ((sine_amp)/(triang_amp)).Varying the modulation index (normally by varying the frequency or amplitude of the triangle wave form) changes that respective modulation index.From personal experience, an appropriate amplitude modulation index for an SPWM waveform should be around 0.8(that is, if the triangle has an amplitude of 10, the sine would have an amplitude of 8). This index should never be equal to 1 (one); it should always be less. A.K.A.: the triangle-wave amplitude should always be greater than the sine-wave.On the other hand, a triangle-wave frequency much greaterthan the sine-wave frequency makes an SPWM that in turn generates a "cleaner" synthesized sine-wave in the H-bridge you are probably using. Try different freq. modulation indexes, but an index of at least 10 should be used (preferably somewhere around 100 if you want a good SPWM). That is, if the sine-wave frequency is 60 Hz, the triangle-wave frequency should be above 600, preferably 6,000 or more. Complications in the filter design in the "output" of the H-bridge will vary greatly when playing around with the frequency modulation index. That being said, keeping the amplitude modulation index at a static 0.8, and playing around with the triangle-wave frequency should be your best bet.
Why is amplitude modulation susceptible to noise but not frequency modulation?
because noise usually changes the amplitude not frequency.
What is the relationship between frequency modulation and the frequency carrier to the modulation index in the AM modulation?
fc>2fm
When modulation frequency is double the modulation index is halF and the modulating voltage remains constant the modulation system is?
frequency modulation..
Define modulation and modulation index?
a measure of the degree of frequency modulation expressed numerically for a pure tone modulation as the ratio of the frequency deviation to the frequency of the modulating signal.
When modulation frequency is doubled the modulation index is halved and the modulating voltage remains constant the modulation system is?
the modulation system is of FM
What is Modulation index formula in Frequency modulation?
mf=(K*Am)/fm where K: is a proprtionality coefficient Am: is amplitude of the message fm=frequency of modulation
What is the deviation ratio for frequency modulation?
Deviation ratio: In a frequency modulation system, the ratio of the maximum frequency deviation of the carrier to the maximum modulating frequency of the system under specified conditions
What is modulation index for frequency modulation?
It varies depending on how strong you want the signal to come through on the receiving end.
What does AM and FM stand for in radios?
AM - Amplitude Modulation FM - Frequency Modulation
What is the unit for modulation index?
Modulation index is also called as Modulation depth. The modulation index of a modulation scheme describes by how much the modulated variable of the carrier signal varies around its unmodulated level.
What is the difference between frequency modulation and phase modulation?
The difference between frequency modulation and phase modulation is that with frequency modulation the angular frequency of the signal is modified while with the phase modulation, the phase angle of the signal is modified.
What does FM stand for in radio frequency?
FM means Frequency Modulated.FM stands for modulation on frequency or frequency modulation.
What is the meaning of FM in FM Radio?
FM means frequency modulation AM means amplitude modulation
