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Spectrum management is a growing problem due to the growing number of spectrum uses. [6] Uses include: over-the-air broadcasting, (which started in 1920); government and research uses (which include defense, public safety—maritime, air, police—resource management, transport, and radio astronomy); commercial services to the public (including voice, data, home networking); and industrial ...
Initially, systems based upon the AMPS mobile phone model were popular, including IS-95 (often known as "CDMA", the air interface technology it uses) and IS-136 (often known as D-AMPS, Digital AMPS, or "TDMA", the air interface technology it uses). Eventually, IS-136 on these frequencies was replaced by most operators with GSM.
Cellular frequencies in the United States are allocated by the US Federal Communications Commission.As cellular mobile telephone technology has evolved over time, periodically bands of frequencies are reassigned from other radio services.
The frequency reuse factor is the rate at which the same frequency can be used in the network. It is 1/K (or K according to some books) where K is the number of cells which cannot use the same frequencies for transmission. Common values for the frequency reuse factor are 1/3, 1/4, 1/7, 1/9 and 1/12 (or 3, 4, 7, 9 and 12, depending on notation ...
Support for both FDD and TDD communication systems as well as half-duplex FDD with the same radio access technology. Support for all frequency bands currently used by IMT systems by ITU-R. Increased spectrum flexibility: 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz and 20 MHz wide cells are standardized.
The term Cellular is sometimes used to describe GSM services in the 850 MHz band, because the original analog cellular mobile communication system was allocated in this spectrum. Further GSM-850 is also sometimes called GSM-800 because this frequency range was known as the "800 MHz band" (for simplification) when it was first allocated for AMPS ...
Radio resource management (RRM) is the system level management of co-channel interference, radio resources, and other radio transmission characteristics in wireless communication systems, for example cellular networks, wireless local area networks, wireless sensor systems, and radio broadcasting networks.
The Global System for Mobile Communications ... Work began in 1991 to expand the GSM standard to the 1800 MHz frequency band and the first 1800 MHz network became ...