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Q: What is the modulation index called when it is expressed as a percentage?
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What is Modulation index in Frequency modulation?

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


What is amplitude modulation derive expression for am wave and modulation index?

the maximum amplitude of carrier wave varied with respect to instantaneous values of message signal is called amplitude modulation


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


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.

Related questions

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.


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.


How the modulation index varies for FM?

how modulation index varies for FM


How modulation index varies for FM?

how modulation index varies for FM


What is Modulation index in Frequency modulation?

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


What is the range of modulation index in am?

The modulation index in AM can range from zero to any number. But if distortion is to be avoided, then the index must not exceed 100%.


What is amplitude modulation derive expression for am wave and modulation index?

the maximum amplitude of carrier wave varied with respect to instantaneous values of message signal is called amplitude modulation


What is percentage power saving if AM transmitter with modulation index m equals 0.5 is replaced by SSBSC transmitter with same modulation index?

Pt=Pc+2Psf, m=0.5 ,Psf=0.0625, saving in power is 100-6.25 % = 94.75%


The values of amplitude modulation index is objective types?

The values of amplitude modulation index is categorized as an objective type.


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..


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