US Patent 7133387 Random access control method for CDMA system

An object of the present invention is to provide an efficient channel access method on the base of propagation delay times in a random access system. The access control method of the present invention for CDMA system wherein a base station is connected with a plurality of mobile stations by the random access is characterized in that the base station stores the propagation delay time of the preamble signal into a memory unit, when the base station transmits a rejection signal for rejecting a communication toward the mobile station which transmits the preamble signal. Further, the base station transmits a allowance signal for allowing a communication toward the mobile station of which propagation delay time is substantially equal to that stored in the memory in the base station.