| abstract |
(57) [Summary] The present invention relates to a process of scheduling an access channel for a radio channel shared by a plurality of mobile devices of a UMTS mobile communication system. This process allows the mobile device to access the base station (BTSC) to signal a dedicated channel assignment request, or in the case of asynchronous inter-cell handover, direct access to a new channel. The process consists in marking the basic TDMA-CDMA frames in multiple frames with independently controllable periodicity and phase. An equal-phase set of marked frames forms a sub-channel shared by the mobile device and performs the particular access type associated with this sub-channel. This access is performed by the mobile by transmitting a code sequence randomly selected from a plurality of different sequences associated with the carriers used in the cell. To mark the frames of the subchannel, use the following type of representation: SFN module [P1] = P2, where SFN is the system frame number and P1 and P2 are the BTSs in the common control channel. The first parameter in the system information message to be advertised by the network or over time are two parameters included in the following messages: paging request, immediate assignment, handover command, uplink free. |