What does quadrature amplitude modulation mean?

Definitions for quadrature amplitude modulation
quad·ra·ture am·pli·tude mod·u·la·tion

This dictionary definitions page includes all the possible meanings, example usage and translations of the word quadrature amplitude modulation.

Wiktionary

  1. quadrature amplitude modulationnoun

    A modulation scheme that conveys data by applying amplitude modulation to two carrier waves at once. These two waves, usually sinusoids, are out of phase with each other by 90° and are thus called quadrature carriers. Commonly abbreviated QAM.

Wikipedia

  1. Quadrature amplitude modulation

    Quadrature amplitude modulation (QAM) is the name of a family of digital modulation methods and a related family of analog modulation methods widely used in modern telecommunications to transmit information. It conveys two analog message signals, or two digital bit streams, by changing (modulating) the amplitudes of two carrier waves, using the amplitude-shift keying (ASK) digital modulation scheme or amplitude modulation (AM) analog modulation scheme. The two carrier waves are of the same frequency and are out of phase with each other by 90°, a condition known as orthogonality or quadrature. The transmitted signal is created by adding the two carrier waves together. At the receiver, the two waves can be coherently separated (demodulated) because of their orthogonality property. Another key property is that the modulations are low-frequency/low-bandwidth waveforms compared to the carrier frequency, which is known as the narrowband assumption. Phase modulation (analog PM) and phase-shift keying (digital PSK) can be regarded as a special case of QAM, where the amplitude of the transmitted signal is a constant, but its phase varies. This can also be extended to frequency modulation (FM) and frequency-shift keying (FSK), for these can be regarded as a special case of phase modulation. QAM is used extensively as a modulation scheme for digital telecommunication systems, such as in 802.11 Wi-Fi standards. Arbitrarily high spectral efficiencies can be achieved with QAM by setting a suitable constellation size, limited only by the noise level and linearity of the communications channel. QAM is being used in optical fiber systems as bit rates increase; QAM16 and QAM64 can be optically emulated with a 3-path interferometer.

Wikidata

  1. Quadrature amplitude modulation

    Quadrature amplitude modulation is both an analog and a digital modulation scheme. It conveys two analog message signals, or two digital bit streams, by changing the amplitudes of two carrier waves, using the amplitude-shift keying digital modulation scheme or amplitude modulation analog modulation scheme. The two carrier waves, usually sinusoids, are out of phase with each other by 90° and are thus called quadrature carriers or quadrature components — hence the name of the scheme. The modulated waves are summed, and the resulting waveform is a combination of both phase-shift keying and amplitude-shift keying, or of phase modulation and amplitude modulation. In the digital QAM case, a finite number of at least two phases and at least two amplitudes are used. PSK modulators are often designed using the QAM principle, but are not considered as QAM since the amplitude of the modulated carrier signal is constant. QAM is used extensively as a modulation scheme for digital telecommunication systems. Arbitrarily high spectral efficiencies can be achieved with QAM by setting a suitable constellation size, limited only by the noise level and linearity of the communications channel.

How to pronounce quadrature amplitude modulation?

How to say quadrature amplitude modulation in sign language?

Numerology

  1. Chaldean Numerology

    The numerical value of quadrature amplitude modulation in Chaldean Numerology is: 2

  2. Pythagorean Numerology

    The numerical value of quadrature amplitude modulation in Pythagorean Numerology is: 9

Translation

Find a translation for the quadrature amplitude modulation definition in other languages:

Select another language:

  • - Select -
  • 简体中文 (Chinese - Simplified)
  • 繁體中文 (Chinese - Traditional)
  • Español (Spanish)
  • Esperanto (Esperanto)
  • 日本語 (Japanese)
  • Português (Portuguese)
  • Deutsch (German)
  • العربية (Arabic)
  • Français (French)
  • Русский (Russian)
  • ಕನ್ನಡ (Kannada)
  • 한국어 (Korean)
  • עברית (Hebrew)
  • Gaeilge (Irish)
  • Українська (Ukrainian)
  • اردو (Urdu)
  • Magyar (Hungarian)
  • मानक हिन्दी (Hindi)
  • Indonesia (Indonesian)
  • Italiano (Italian)
  • தமிழ் (Tamil)
  • Türkçe (Turkish)
  • తెలుగు (Telugu)
  • ภาษาไทย (Thai)
  • Tiếng Việt (Vietnamese)
  • Čeština (Czech)
  • Polski (Polish)
  • Bahasa Indonesia (Indonesian)
  • Românește (Romanian)
  • Nederlands (Dutch)
  • Ελληνικά (Greek)
  • Latinum (Latin)
  • Svenska (Swedish)
  • Dansk (Danish)
  • Suomi (Finnish)
  • فارسی (Persian)
  • ייִדיש (Yiddish)
  • հայերեն (Armenian)
  • Norsk (Norwegian)
  • English (English)

Word of the Day

Would you like us to send you a FREE new word definition delivered to your inbox daily?

Please enter your email address:


Citation

Use the citation below to add this definition to your bibliography:

Style:MLAChicagoAPA

"quadrature amplitude modulation." Definitions.net. STANDS4 LLC, 2024. Web. 17 Jul 2024. <https://www.definitions.net/definition/quadrature+amplitude+modulation>.

Discuss these quadrature amplitude modulation definitions with the community:

0 Comments

    Are we missing a good definition for quadrature amplitude modulation? Don't keep it to yourself...

    Image or illustration of

    quadrature amplitude modulation

    Credit »

    Free, no signup required:

    Add to Chrome

    Get instant definitions for any word that hits you anywhere on the web!

    Free, no signup required:

    Add to Firefox

    Get instant definitions for any word that hits you anywhere on the web!

    Browse Definitions.net

    Quiz

    Are you a words master?

    »
    relating to a technique that does not involve puncturing the skin or entering a body cavity
    A frantic
    B noninvasive
    C hatched
    D sought

    Nearby & related entries:

    Alternative searches for quadrature amplitude modulation: