Broadcast control channel

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A broadcast control channel (BCCH) is a point to multipoint, unidirectional (downlink) channel used in the Um interface of the GSM cellular standard. The BCCH carries a repeating pattern of system information messages that describe the identity, configuration and available features of the base transceiver station (BTS). These messages also provide a list of absolute radio-frequency channel numbers (ARFCNs) used by neighboring BTSs. This message pattern is synchronized to the BTS frame clock. [1] The minimum BCCH message set is system information messages 2–4, although other messages are normally present. The messages themselves are described in 3GPP Technical Specification 44.018. [2]

Any GSM ARFCN that includes a BCCH is designated as a beacon channel and is required to transmit continuously at full power.

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References

  1. "GSM 3GPP Technical Specification 45.002 (Section 6.3.1.3)". 3rd Generation Partnership Project (3GPP ). Retrieved 2010-05-10.
  2. "GSM 3GPP Technical Specification 44.018 (sections 9.1.31-9.1.43k)". 3rd Generation Partnership Project (3GPP ). Retrieved 2010-05-10.