A METHOD OF EFFECTING RANDOM ACCESS IN A MOBILE RADIO SYSTEM

摘要

A method for random access in a time divided mobile radio system, for instance an FDMA/TDMA system, which includes digital traffic channels and control channels which are organized so that four traffic channels and two control channels are included in a TDMA-frame. A base station transmits continuously flags in the time slots of the control channels. A mobile station desiring access to the system responds by sending a first message word in the time slot indicated by the base station in a first flag. When the mobile station wishes to transmit several message words, the base station reserves one or more time slots to this end by transmitting the first flag, although this flag now states that these time slots are busy for other mobile stations. Furthermore, the base station transmits a flag which states whether or not a message word has been received from the mobile station. The base station can transmit a further flag, which denotes that a given time slot has been reserved for a given mobile station from the very beginning of an access procedure and cannot therefore be used by any other mobile station.