Common Control Channels

  To or from a certain BTS to a single mobile 

*  Paging Channel (PCH) 

        BTS Transmits a paging message to indicate an incoming call or 

        short message. The paging message contains the identity number 

        of the mobile subscriber that the network wishes to contact. (DL) 

*  Random Access Channel (RACH) 

        MS Answers paging message on the RACH by requesting a signaling 

        channel of SDCCH.  (UL) 

*  Access Grant Channel (AGCH) 

        Assigns a signaling channel (SDCCH) to the MS. (BCH)or as it called (DL)