Amplitude modulation – Definition & Meaning

Amplitude modulation (AM) is a method of transmitting signals through radio waves by varying the amplitude of the carrier wave in proportion to the modulating signal. It is one of the oldest and most commonly used techniques for radio broadcasting and is widely used in both commercial and military applications.

Definitions

Amplitude modulation is the process of varying the amplitude of a carrier wave in accordance with the amplitude of a modulating signal. In simpler terms, it is the process of changing the strength of a radio wave to carry information.

Origin

Amplitude modulation was first used in the early 1900s by radio pioneers such as Reginald Fessenden, who used it to transmit voice signals over long distances. The technique became popular in the 1920s and 1930s with the advent of commercial radio broadcasting.

Meaning in different dictionaries

According to the Merriam-Webster dictionary, amplitude modulation is “the modulation of a radio wave by varying its amplitude in accordance with the amplitude of a modulating wave.” The Oxford English Dictionary defines it as “the variation of the amplitude of a carrier wave in accordance with the amplitude of a modulating signal.”

Associations

Amplitude modulation is often associated with radio broadcasting, as it is the most common method used to transmit radio signals. It is also used in other applications such as radar, where it is used to measure the distance and speed of objects.

Synonyms

Synonyms of amplitude modulation include AM, modulation, and amplitude shift keying (ASK).

Antonyms

Antonyms of amplitude modulation include frequency modulation (FM) and phase modulation (PM).

The Same Root Words of Amplitude Modulation

The same root words of amplitude modulation include amplitude, which refers to the maximum displacement of a wave from its equilibrium position, and modulation, which refers to the process of varying a wave in some way.

Example Sentences

1. The radio station uses amplitude modulation to transmit its signal.
2. Amplitude modulation is an important technique in radar systems.
3. The strength of the radio signal is controlled by the amplitude modulation process.
4. Amplitude modulation is a simple but effective method for transmitting information over long distances.
5. The modulating signal is used to vary the amplitude of the carrier wave in amplitude modulation.