To allow a terminal to exchange signal information with a base station allocated by using a different method by receiving a signal sequence at first and then rejecting or approving a channel capacity request from a certain terminal through a channel to be collectively used by a plurality of terminals.

Termianls 4 to 7 allocated to a base station 1 transmit the same signal sequences at different points of time. A different base station allocates a different signal sequence to the above allocated registered terminals 4 to 7. When a terminal is moved from a certain radio cell to another radio cell, the terminal registered in two base stations transmits a signal sequence for previously determining a base station at its user channel. The base station 1 includes a matching filter and a peak detector for detecting a signal sequence. The signal sequence has only a small correlation with another signal to be transmitted in a network and can be transmitted at optical sequence start time.