Definition

Noun: 1. A method of transmitting information via a radio wave: Amplitude modulation (AM) is a technique where the strength (amplitude) of a continuous radio wave (the carrier wave) is varied in proportion to the signal being sent, such as sound from a microphone. This encodes the information onto the wave for transmission.

Usage

• General Use: The term is used in telecommunications, broadcasting, and electronics to describe this specific modulation technique. : Traditional AM radio broadcasting uses amplitude modulation to send audio signals over long distances. : The engineer explained how amplitude modulation differs from frequency modulation in its susceptibility to static.

Advanced Usage

• Technical Context: In technical specifications and discussions, "amplitude modulation" often appears in its abbreviated form, "AM," and is contrasted with other methods like FM (frequency modulation). : The receiver was set to demodulate the amplitude modulation signal from the 1 MHz carrier.
• "Amplitude-modulated" (Adjective): Describes a signal or wave that has undergone this process. : An amplitude-modulated carrier contains sidebands that carry the information.

Variants and Related Words

• AM: The common abbreviation for amplitude modulation.
• Amplitude-Modulated (adj): The adjectival form describing the state of the wave.
• Modulation (n): The general process of varying a wave to encode information. Amplitude modulation is one type.
• Carrier Wave (n): The base radio wave that is modulated.

Synonyms

• AM: (The direct abbreviation, used interchangeably in many contexts).

Related Phrases and Concepts

• Sidebands: The frequency bands produced on either side of the carrier frequency during amplitude modulation, containing the signal information.
• Demodulation: The process of extracting the original information signal from an amplitude-modulated wave.

Noun

1. modulation of the amplitude of the (radio) carrier wave