In
telecommunications
Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of ...
, the term fade margin (fading margin) has the following meanings:
*A design allowance that provides for sufficient
system
A system is a group of interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its open system (systems theory), environment, is described by its boundaries, str ...
gain or
sensitivity to accommodate expected
fading
In wireless communications, fading is the variation of signal attenuation over variables like time, geographical position, and radio frequency. Fading is often modeled as a random process. In wireless systems, fading may either be due to mul ...
, for the purpose of ensuring that the required
quality of service
Quality of service (QoS) is the description or measurement of the overall performance of a service, such as a telephony or computer network, or a cloud computing service, particularly the performance seen by the users of the network. To quantitat ...
is maintained.
*The amount by which a
received signal level may be reduced without causing system performance to fall below a specified threshold value. It is mainly used to describe a communication system such as
satellite
A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scient ...
, for example a system like
globalstar
Globalstar, Inc. is an American telecommunications company that operates a satellite constellation in low Earth orbit (LEO) for satellite phone, low-speed data transmission and earth observation. The Globalstar second-generation constellation con ...
operates at 25-35 dB Fade margin.
See also
*
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 ...
*
Link Budget
A link budget is an accounting of all of the power gains and losses that a communication signal experiences in a telecommunication system; from a transmitter, through a communication medium such as radio waves, cables, waveguides, or optic ...
References
*Attila Hilt, "Availability and Fade Margin Calculations for 5G Microwave and Millimeter-Wave Anyhaul Links", Applied Sciences, 2019, 9(23), 5240; https://doi.org/10.3390/app9235240.,
Trevor Manning, "Microwave Radio Transmission Design Guide", 2nd edition; Artech House: London, UK, 2009.
{{Two-way radio
Radio frequency propagation fading