Modulation is the process of converting data into radio waves by adding information to an electronic or optical carrier signal. In computer networks, modulation is used to convert digital signals into analog signals for transmission over a medium. The most commonly used types of modulation in computer networks include:
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Amplitude Modulation (AM): In this type of modulation, only the amplitude of the carrier signal is varied to represent the data being added to the signals, while the phase and the frequency of the signal are kept unchanged.
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Frequency Modulation (FM): In FM, only the frequency of the carrier signal is varied to represent the frequency of the data, while the phase and the amplitude of the signals are kept unchanged.
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Phase Modulation (PM): In PM, the phase of the carrier signal is varied to represent the data being added to the signal. Different information values are represented by different phases.
Modulators and demodulators are devices or chips or components that convert analog signals into digital signals and digital signals into analog signals, respectively. A modem is a device that performs both modulation and demodulation processes. Through data modulation, computers can send digital signals on a medium that can only carry analog signals, such as telephone lines.
