amplitude modulation: meaning, definition, pronunciation and examples
C1-C2Technical, Scientific, Electronics
Quick answer
What does “amplitude modulation” mean?
A method of encoding information onto a radio wave by varying its strength (amplitude) while keeping its frequency constant.
Audio
Pronunciation
Definition
Meaning and Definition
A method of encoding information onto a radio wave by varying its strength (amplitude) while keeping its frequency constant.
The process of varying the amplitude of a carrier signal in proportion to the instantaneous amplitude of the message signal. Often used to transmit audio signals via radio broadcast, specifically in the AM radio band.
Dialectal Variation
British vs American Usage
Differences
No significant lexical differences; the term is identical in both varieties. The abbreviation 'AM' is universal, but the long-form term is used in identical contexts.
Connotations
The term is purely technical with no cultural or emotional connotations. It may be associated with older radio technology, static, and talk radio/weather reports in both cultures.
Frequency
The full term 'amplitude modulation' is used less frequently in everyday conversation than the abbreviation 'AM'. It is most common in technical writing, manuals, and academic contexts in both the UK and US.
Grammar
How to Use “amplitude modulation” in a Sentence
[carrier wave] undergoes amplitude modulation by [signal][signal] is transmitted via amplitude modulationThe [device] uses amplitude modulation for [purpose]Vocabulary
Collocations
Examples
Examples of “amplitude modulation” in a Sentence
verb
British English
- The signal needs to be amplitude-modulated before transmission.
- We amplitude-modulate the carrier with the audio input.
American English
- The engineers amplitude-modulated the carrier wave.
- This circuit is designed to amplitude-modulate the signal.
adjective
British English
- We studied amplitude-modulation techniques.
- The amplitude-modulation receiver was prone to static.
American English
- They sent an amplitude-modulation signal.
- The old amplitude-modulation equipment is in the museum.
Usage
Meaning in Context
Business
Rare, except in contexts like broadcasting company strategy ('We are divesting our AM radio assets.')
Academic
Central in physics, engineering, and telecommunications courses, textbooks, and research papers.
Everyday
Minimal; encountered mainly when discussing radio bands ('I listen to the news on AM.') but not the full term.
Technical
The primary context. Used in electronics design, radio engineering, signal processing, and communication theory.
Vocabulary
Synonyms of “amplitude modulation”
Neutral
Weak
Vocabulary
Antonyms of “amplitude modulation”
Watch out
Common Mistakes When Using “amplitude modulation”
- Pronouncing 'modulation' as /mɒˈdjuːl/ instead of /ˌmɒdjʊˈleɪʃ(ə)n/.
- Using it as a verb ('to amplitude modulate' is correct but hyper-technical).
- Incorrectly writing it as 'amplification modulation'.
- Confusing it with 'analog modulation' (which is a broader category).
FAQ
Frequently Asked Questions
AM stands for Amplitude Modulation.
FM (Frequency Modulation) generally provides better sound quality because it is less susceptible to amplitude-based noise like static from electrical storms or machinery.
AM signals can travel much farther, especially at night, and can cover wider geographical areas with fewer transmitters. The lower sound fidelity is less critical for speech than for music.
Yes, but it's highly technical. The verb form is 'to amplitude-modulate' (e.g., 'The circuit amplitude-modulates the carrier'). In everyday language, people just say 'use AM' or 'broadcast on AM'.
A method of encoding information onto a radio wave by varying its strength (amplitude) while keeping its frequency constant.
Amplitude modulation is usually technical, scientific, electronics in register.
Amplitude modulation: in British English it is pronounced /ˈæmplɪtjuːd ˌmɒdjʊˈleɪʃ(ə)n/, and in American English it is pronounced /ˈæmplɪtuːd ˌmɑːdʒəˈleɪʃ(ə)n/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Imagine a DJ turning the VOLUME KNOB up and down on a steady tone to encode a message—varying the AMPLITUDE. That's AM-plitude Modulation.
Conceptual Metaphor
A CARRIER WAVE is a CANVAS; the MESSAGE SIGNAL is the PAINT applied by varying the THICKNESS (amplitude) of the paint.
Practice
Quiz
What is the primary technical disadvantage of amplitude modulation (AM) compared to frequency modulation (FM)?