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In addition to radio frequencies used to connect handsets with cellular base stations, other parts of the radio spectrum are used to interconnect base stations and the wired telephone network. Some frequency bands may be vulnerable to interference by existing services in adjacent frequency bands, such as UHF television broadcasting.
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 ...
US frequency allocations chart, 2016. Frequency allocation ... Cellular AMPS 806–947 0.003 .33 Amateur Land mobile GPS 1200–1600 .23 Cellular PCS 1700–2000
GSM had already been running for some time on US PCS (1,900 MHz) frequencies. And, some NMT-450 analog networks have been replaced with digital networks using the same frequency. In Russia and some other countries, local carriers received licenses for 450 MHz frequency to provide CDMA mobile coverage area.
TETRA uses different channel spacing compared to GSM systems. The standard is 25 kHz spacing and the center frequency of each channel may be offset in a number of fashions such as ±12.5 kHz or even ±6.25 kHz. This makes it more tricky to correlate the ARFCN strictly to a pair of frequencies, you need to know the specifics of the system.
For mobile phone technology, a mobile allocation index offset (MAIO) refers a time delay separating traffic channels.When a GSM (Global System for Mobile Communications) mobile phone is served by a cell that is hopping over a set of frequencies, the separate traffic channels hop over the allocated frequencies according to a hopping sequence number (HSN).
Information in this chart supersedes that in File:United States Frequency Allocations Chart 2011 - The Radio Spectrum.pdf. Archived at archive.org on 2016-10-30. Licensing
CDMA cellular systems can allow an increase in traffic capacity at the expense of the quality of service. [3] In TDMA/FDMA cellular radio systems, Fixed Channel Allocation (FCA) is used to allocate channels to customers. In FCA the number of channels in the cell remains constant irrespective of the number of customers in that cell.