Communications Toolbox

Digital Modulation

Like analog modulation, digital modulation alters a transmittable signal according to the information in a message signal. However, in this case, the message signal is restricted to a finite set. Using this toolbox, you can modulate or demodulate signals using various digital modulation techniques, listed in Modulation Features of the Toolbox. You can also plot signal constellations.

Note   The modulation and demodulation functions do not perform pulse shaping or filtering. See Special Filters or Combining Pulse Shaping and Filtering with Modulation for more information about filtering.

The topics in this section are as follows:

• Representing Digital Signals

• Baseband Modulated Signals Defined

• Examples of Digital Modulation and Demodulation

• Plotting Signal Constellations

Analog Modulation Example

Representing Digital Signals

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