what is modulation

Modulation is the process of varying one or more properties of a periodic waveform, known as the carrier signal, with a separate signal called the modulation signal that typically contains information to be transmitted. It involves converting data into radio waves by adding information to an electronic or optical carrier signal. This process allows for the transmission of multiple channels of information through a single communication medium, using techniques such as frequency-division multiplexing (FDM) . Modulation can be applied to electromagnetic signals, such as radio waves, lasers/optics, and computer networks, and even to a direct current by turning it on and off, as in Morse code telegraphy or a digital current loop interface. There are different types of modulation, including amplitude modulation (AM), frequency modulation (FM), and phase modulation. Modulation is essential for increasing the reach of signals and enabling fast transmission of information, playing a major role in the development of wireless communication systems. It is also used to alter the characteristics of carrier waves, such as amplitude, frequency, and phase, and can be analog or digital. Overall, modulation is a fundamental process that enables the transmission of information over various communication mediums.