Modulation

Last Updated: April 9, 2013

Definition - What does Modulation mean?

Modulation is a process through which audio, video, image or text information is added to an electrical or optical carrier signal to be transmitted over a telecommunication or electronic medium. Modulation enables the transfer of information on an electrical signal to a receiving device that demodulates the signal to extract the blended information.

Techopedia explains Modulation

Modulation is primarily used in telecommunication technologies that require the transmission of data via electrical signals. It is considered the backbone of data communication because it enables the use of electrical and optical signals as information carriers. Modulation is achieved by altering the periodic waveform or the carrier. This includes carrying its amplitude, frequency and phase. Modulation has three different types:

Amplitude Modulation (AM): Amplitude of the carrier is modulated.
Frequency Modulation (FM): Frequency of the carrier is modulated.
Phase Modulation (PM): Phase of the carrier is modulated.

A modem is a common example/implementation of a modulation technique in which the data is modulated with electrical signals and transmitted over telephone lines. It is later demodulated to receive the data.