noun Electronics, Radio.
- 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 signalAbbreviation: AM, am Compare frequency modulation
- a wave that has undergone this process
- 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. Compare frequency modulation.