FIELD: mobile radio communication systems with time-shared channels. SUBSTANCE: base station continuously transmits flags (B/I, R/N, R/F) during time spaces of control channels. Mobile station that wants to acquire access to system responds by sending first word of message (W1) during time space indicated by base station in first flag (B/I). When mobile station has to transmit more than one word of message, (W2, W3), base station backs up one or more time spaces for it by transmitting flag (B/O). This flag shows that mentioned time spaces are busy for other mobile stations. In addition, base station transmits flag (R/N) which indicates if message word is received from mobile station. Base station can transmit one more flag (R/F) which shows that given time space was backed up for given station since very beginning of access and, consequently, it cannot be used by any other transmitting station. EFFECT: improved reliability of direct access to mobile radio communication system. 8 cl, 9 dwg
