A method and system for configuring a radio interface between a mobile station and a base station in a time-division multiplex mobile radio system for packet data transmission, wherein time slots for signalling are allocated by the base station to the mobile stations in accordance with a sequence which can be predetermined, independent of packet data transmission. The time for configuration of the radio interface also can be reduced by a plurality of time slots for signalling being combined to form a signalling block, or the signalling to a plurality of mobile stations being carried out within one time slot. This signalling is used to define and set the timing advance.