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  2. Fading - Wikipedia

    en.wikipedia.org/wiki/Fading

    In wireless systems, fading may either be due to multipath propagation, referred to as multipath-induced fading, weather (particularly rain), or shadowing from obstacles affecting the wave propagation, sometimes referred to as shadow fading. A fading channel is a communication channel that experiences fading.

  3. Channel state information - Wikipedia

    en.wikipedia.org/wiki/Channel_state_information

    In wireless communications, channel state information (CSI) is the known channel properties of a communication link.This information describes how a signal propagates from the transmitter to the receiver and represents the combined effect of, for example, scattering, fading, and power decay with distance.

  4. Rayleigh fading - Wikipedia

    en.wikipedia.org/wiki/Rayleigh_fading

    Rayleigh fading is a statistical model for the effect of a propagation environment on a radio signal, such as that used by wireless devices.. Rayleigh fading models assume that the magnitude of a signal that has passed through such a transmission medium (also called a communication channel) will vary randomly, or fade, according to a Rayleigh distribution — the radial component of the sum of ...

  5. Fade margin - Wikipedia

    en.wikipedia.org/wiki/Fade_margin

    In telecommunications, the term fade margin (fading margin) has the following meanings: A design allowance that provides for sufficient system gain or sensitivity to accommodate expected fading , for the purpose of ensuring that the required quality of service is maintained.

  6. Multipath propagation - Wikipedia

    en.wikipedia.org/wiki/Multipath_propagation

    In radio communication, multipath is the propagation phenomenon that results in radio signals reaching the receiving antenna by two or more paths. Causes of multipath include atmospheric ducting, ionospheric reflection and refraction, and reflection from water bodies and terrestrial objects such as mountains and buildings.

  7. Spread spectrum - Wikipedia

    en.wikipedia.org/wiki/Spread_spectrum

    Techniques known since the 1940s and used in military communication systems since the 1950s "spread" a radio signal over a wide frequency range several magnitudes higher than minimum requirement. The core principle of spread spectrum is the use of noise-like carrier waves, and, as the name implies, bandwidths much wider than that required for ...

  8. Weibull fading - Wikipedia

    en.wikipedia.org/wiki/Weibull_fading

    Weibull fading, named after Waloddi Weibull, is a simple statistical model of fading used in wireless communications and based on the Weibull distribution. Empirical studies have shown it to be an effective model in both indoor [ 1 ] and outdoor [ 2 ] environments.

  9. Shadowing - Wikipedia

    en.wikipedia.org/wiki/Shadowing

    Shadow fading in wireless communication, caused by obstacles; File shadowing, to provide an exact copy of or to mirror a set of data; Job shadowing, learning tasks by first-hand observation of daily behavior; Projective shadowing, a process by which shadows are added to 3D computer graphics