|amplitude modulation |
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.
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).)