What is modulation?

Galina Mirzahmedova
Galina Mirzahmedova
May 16, 2015
What is modulation?

In physics, the term modulation is used.

Most often it is used to describe signals or waves, but it is also found in music, although, in fact, the voice or the sound of a musical instrument is also a sound wave.

What is modulation in physics?

Modulation is the process of changing a single or two or more signal parameters (sound and other waves) in the instantaneous value of an information signal. What is modulation in radio engineering: it is a process that allows you to transfer a signal to a region of lower or higher frequencies for a specific purpose. With modulation, you can achieve the following goals:

  • make the signal more resistant to interference;
  • compare the line and signal parameters;
  • transmit signals over longer distances;
  • create transmission systems that contain several channels.

Modulation Types

There are several main types of modulation depending on the parameters of the change:

  • pulse frequency - the frequency of transmission of pulses of a given signal changes;
  • pulse amplitude - modulation of the parameters of the amplitude of the transmitted pulses of a given signal;
  • pulse width - change the duration of the pulsed signal;
  • phase pulse - change the phase of a given signal pulse.

Modulation in music

In music, modulation is also used during the performance of various musical works and during singing. It consists in the transition from one tonality to another (decrease, increase). Moreover, the modulation can be both between the closest and between more distant tonalities. The latter is performed by using a common chord in the key data.

Speech words

The word "modulation" can be used, for example, in such a sentence: "Depending on the parameters of the change, frequency, amplitude, latitude and phase-pulse modulation are distinguished."