DCS-1800 is a Pan-European Digital Personal Communications System operating at 1800 MHz. Adopted by the U.K. Personal Communications Networks (PCN) operators, it is derived from GSM-900 with adaptation of radio parameters to suit micro-cellular systems. Major differences include the use of lower power transmitters in both the mobile units and the base stations, and operation at 1.8 GHz rather than 900 MHz. DCS-1800 is sometimes referred to as PCN.
The vision of PCN is to be a provider of high-quality two-way communications services -- both for speech and data -- to both business users and consumers on the move, outdoors and indoors. Low cost, low power, highly portable handsets and close-proximity working are viewed as primary differences from cellular networks. Stationary or slow (e.g. walking) speed use appropriate for a micro-cellular system is expected in contrast to high speed (automobile speed) use requiring a macro-cellular structure.
The relatively low output power of PCN systems coupled with the requirement for a highly portable handset has lead to a preference for 3 volt design in these systems.
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