Modulate using frequency modulation

Analog Passband Modulation, in Modulation

The FM Modulator Passband block modulates using frequency modulation. The output is a passband representation of the modulated signal. The output signal's frequency varies with the input signal's amplitude. Both the input and output signals are real scalar signals.

If the input is *u*(*t*)
as a function of time *t*, then the output is

$$\mathrm{cos}\left(2\pi {f}_{c}t+2\pi {K}_{c}{\displaystyle {\int}_{0}^{t}u(\tau )d\tau +\theta}\right)$$

where:

*f*_{c}represents the**Carrier frequency**parameter.$$\theta $$ represents the

**Initial phase**parameter.*K*_{c}represents the**Frequency deviation**parameter.

Typically, an appropriate **Carrier frequency** value
is much higher than the highest frequency of the input signal.

By the Nyquist sampling theorem, the reciprocal of the model's
sample time (defined by the model's signal source) must exceed twice
the **Carrier frequency** parameter.

This block works only with real inputs of type `double`

.
This block does not work inside a triggered subsystem.

**Carrier frequency (Hz)**The frequency of the carrier.

**Initial phase (rad)**The initial phase of the carrier in radians.

**Frequency deviation (Hz)**The frequency deviation of the carrier frequency in Hertz. Sometimes it is referred to as the "variation" in the frequency.

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