# index of modulation

## Definitions

### Electronics

- A measure of the degree of modulation, usually involving the ratio of a peak variation to a steady non-peak value. The result may be multiplied by 100 to obtain a percentage.
- In
__frequency__ modulation, the ratio of the peak variation of the carrier wave frequency, to the frequency of the modulating signal. The result may be multiplied by 100 to obtain a percentage. - In amplitude modulation, the
__peak amplitude__ variation of the composite wave, to the unmodulated carrier amplitude. The result may be multiplied by 100 to obtain a percentage. - In amplitude modulation, the ratio of half the
__difference__ between the __maximum__ amplitude and minimum amplitude, to the average amplitude. The result may be multiplied by 100 to obtain a percentage.

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