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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 ...
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 increased capacity in a cellular network, compared with a network with a single transmitter, comes from the mobile communication switching system developed by Amos Joel of Bell Labs [5] that permitted multiple callers in a given area to use the same frequency by switching calls to the nearest available cellular tower having that frequency ...
Mobile networks based on different standards may use the same frequency range; for example, AMPS, D-AMPS, N-AMPS and IS-95 all use the 800 MHz frequency band. Moreover, one can find both AMPS and IS-95 networks in use on the same frequency in the same area that do not interfere with each other.
The NTIA's Office of Spectrum Management [6] is in charge of regulating use of spectrum allocated to the federal government. It serves in a manner equivalent to the Federal Communications Commission for this purpose. The OSM carries out the responsibilities of managing the radio frequency spectrum by: [6]
Code-division multiple access (CDMA) is a channel access method used by various radio communication technologies. CDMA is an example of multiple access, where several transmitters can send information simultaneously over a single communication channel.
Frequency-hopping spread spectrum (FHSS) is a method of transmitting radio signals by rapidly changing the carrier frequency among many frequencies occupying a large spectral band. The changes are controlled by a code known to both transmitter and receiver .
The radio frequency spectrum is a limited natural resource which is increasingly in demand from a large and growing number of services such as fixed, mobile, broadcasting, amateur, space research, emergency telecommunications, meteorology, global positioning systems, environmental monitoring and communication services – that ensure safety of ...