amplitude modulation

British  

noun

1. Abbreviation: AM.   am.  one of the principal methods of transmitting audio, visual, or other types of information using radio waves, the relevant signal being superimposed onto a radio-frequency carrier wave. The frequency of the carrier wave remains unchanged but its amplitude is varied in accordance with the amplitude of the input signal Compare frequency modulation

2. a wave that has undergone this process

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amplitude modulation Scientific  

1. A method of transmitting signals, such as sound or digital information, in which the value of the signal is given by the amplitude of a high frequency carrier wave. In AM radio transmission, for example, the signal to be carried is a sound wave, and its increasing and decreasing value is reflected in the increasing and decreasing amplitude of the radio frequency carrier wave. In fiber optics, the carrier wave is a beam of light.

2. Compare frequency modulation

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amplitude modulation Cultural  

1. A type of radio signal in which the amplitude, or strength, of a radio wave is varied in order to carry information from a transmitter to a receiver. (Compare frequency modulation (FM).)

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Example Sentences

By contrast, the amplitude modulation of speech is typically 4-5 Hz, meaning its volume changes frequently.

From Science Daily • May 28, 2024

AM stands for amplitude modulation, used to transmit information in a radio wave.

From Los Angeles Times • Jul. 31, 2023

The difference between AM, or amplitude modulation, and FM, or frequency modulation, involves how sound waves are encoded into a signal that can be picked up by receivers.

From Washington Times • Jun. 6, 2023

The abbreviation AM stands for amplitude modulation, which is the method for placing information on these waves.

From Textbooks • Aug. 12, 2015

Eight of the targets showed a definite amplitude modulation on the echo.

From Pushbutton War by Schoenherr, John