FIELD: establishing communications by allocating common-user channel. SUBSTANCE: mobile station has common-user channel message sending device incorporating message generator producing frame stream, each including pointer field and data field, by dividing data stream to be transferred, inserting end-of-frame pointer in last frame pointed filed, and inserting continued-frame pointer in each pointer field of frames other than last one; it also has common-user backward channel transmitter that functions to transmit generated message. Base station has device for receiving common-user channel message transferred from mobile station that incorporates common-user channel receiver and message processor for checking pointer filed inserted in common- user backward channel frame being received and deallocating common-user backward channel when pointer field indicates end frame of common-user backward channel. EFFECT: enhanced effectiveness of common-user backward control channel application. 27 cl, 7 dwg
